Friday, December 30, 2005

Walking Pants (Invisible Man) Breakdown Video Part 1

This is a video podcast breaking down a commercial I did. We see a walking pair of pants and a man with no pants in this invisible man type of spot. I discuss some possible approaches in this first part.

(Now updated with YouTube)



Next part:
Pants breakdown Part 2

Thursday, December 29, 2005

Bandwidth issues

Evidently the podcasts have been doing too well. My service provider has warned me that I may be exceeding their bandwidth so I may have to move the files elsewhere. If you have suggestions for responsive web service providers that provide large storage and large bandwidth (without breaking the bank) let me know via email. You can click on profile on right and click on email.

[My service provider stopped my file transfers. I'm hoping to have podcasts available again after midnight tonight. I've had to remove the video cast for now]

Wednesday, December 28, 2005

Walking Pants (Invisible Man) Breakdown Video



[ Notice: I've reposted this in two parts. Look at the later postings.
Pants breakdown Part 1
]

[Notice: I've had to remove this file since it and the other podcasts are exceeding my bandwidth. I'll re-post once I locate a place that has large bandwidth and storage]

This is a video podcast breaking down a commercial I did. We see a walking pair of pants and a man with no pants in this invisible man type of spot. I discuss some possible approaches and then do a breakdown of key shots. Breakdown starts at 15:53.
This is encoded at 1/2 video res, h264 (ipod video format). You may need QuickTime 7 to view. Even at that it's almost 100MB for 36 minutes.
Let me know what you think. Thanks.

Saturday, December 24, 2005

Happy Holidays

Happy Holidays to all.

I'm working on a video cast and had hoped to have it up by now but it'll probably be a few more days.

Wednesday, December 14, 2005

Visual Effects Career

Getting started in a career in Visual Effects.


[For anyone considering visual effects career please check out this article:
VFX in Los Angeles – 100 hour weeks & homeless  Puts things in perspective.  Much has changed from when I wrote the original article]


The pros and cons as well as learning and applying for jobs.

1:39 The Upside
2:49 The Downside
7:30 Education
13:04 Self Education
14:33 Hands on
17:58 On the job training
18:32 Company Projects
19:49 Hiring practices
20:50 Applying for a job
23:21 Demo Reels

Transcript:

Today I'll be talking about Visual Effects Careers. This is primarily for those considering visual effects careers but there may be some items of value for those already in the business.

The big question
The first question is do you really want to do Visual Effects for a living.
Just because it sounds kind of cool isn't a good enough reason.

Fame and fortune – forget it, this is not the place for either of these.

If your main goal is to do something else such as direct or write I would not suggest starting in visual effects. It's no shortcut to other jobs in the industry, especially since you're exposure to the live action side of production will be minimal.

The upside:

If you enjoy creating visuals whether it's art or photography then visual effects can be a good fit.
Moving images can be very compelling and provide even more room for creativity.
It involves technology and problem solving with art so can be rewarding for those who have an interest in both of these areas and like a challenge.
There's a wide range of jobs from computer programming to art direction so your interest level can be quite diverse.
There's certainly a sense of accomplishment when you finish a shot and a project.
Your work is likely to be seen by millions of people whether it's a commercial or a feature film.
If it's a feature or TV show there's a record of your work in the form of a DVD that others can still see years later.
The work is usually a combination of individual and teamwork.
Each show and most shots have different challenges so you're not likely to be bored.
The money is good.

The downside:
Some people work 8 hours a day in this field but most work 10 to 12 hours a day. That's 50 to 60 hours for a 5-day week. The number of hours can go up toward the end of a project. If you're involved in live action shooting you'll be working 12-hour days. That's 50% more hours a day than a typical job.

Sometimes you have to work Saturdays and even some Sundays, especially toward the end of the project. I worked 90 days straight at 12 hours a day at the end of Star Trek The Motion Picture. I've also worked a few 24-hour days. Luckily it's usually not quite that crazy in the digital age. [Update: It's actually now worse in the digital age than it was before. 24hr work days not as rare as they once were. Certainly 16-18hr days are on the rise.] Needless to say this can put a damper on social events such going to concerts or sporting events. If you're married it can be difficult on you and your family. If you're not married it can be difficult to have a social life

There are only a few locations where visual effects for features are done on a large scale. Los Angeles, San Francisco, London and New Zealand are the largest. There are other pockets of work throughout the world, especially if you work in TV or commercials. That means it's likely you'll need to relocate to one of these metropolitan areas with all their pros and cons. Some of the downsides include a higher cost of living and heavy traffic with longer commute times. 12-hour days combined with an hour travel to work and hour back gives you only 10 hours to sleep and spend time with your family.

In the future more work may be able to be outsourced so it may become possible to live elsewhere. Some matte painters are able to do this.

In the digital age you will probably spend the majority of your time sitting in front of a monitor working on very detailed issues.

Much of the work is ultimately freelance. You may get a staff job at an effects facility but a sizable number of people are hired on a project-by-project basis. . You may work long days at the end of a project and have no break to the next project or you could find yourself out of work for 6 months. How much you work at one facility will be dependent on how efficient management is on obtaining new projects and scheduling them.

You may have to switch to different companies to keep working. This is when it becomes problematic to be working in a location with only 1 or 2 effects companies. You'll need to make contacts and start developing a credit list to try to keep working. The higher level you go (such as an animation lead) the less number of jobs there are available. It's not unusual for a director of photography to be without work for 1 to 2 years. So keep that in mind when looking at wages. This also causes problems maintaining health insurance. ILM is one of the few places (maybe the only place?) that have some of their employees, including CG, in a union. One of the reasons for Hollywood unions is to allow for the freelance nature of this business.

The business of visual effects goes through cycles of feast or famine. You may get multiple job offers one week and at other times there may not be anything available for 6 or more months. Some facilities reduce to a skeleton staff just to keep the doors open when there's no work. Other times they'll be turning down work since they can't expand and handle it.

Even with the expanding need for content, the number of jobs available is less than the number of people trying to break in. This is probably better than filmmaking in general where hundreds of schools are now producing thousands of film school graduates for a very limited number of jobs.

Out sourcing- with the speed of the Internet it's becoming easier for companies to start outsourcing work to less expensive locations such as Asia. This happened with 2D animation and now the same process is occurring for 3D animation and lower level or entry-level visual effects jobs.

[Update 8/8/2010 - Be sure to check out the links on the right under the heading VFX INDUSTRY - STATE OF THE INDUSTRY.  All of these are worth reading for those considering visual effects as a career. Today there is much more outsourcing and more work going outside the US due to tax incentives and other factors. How easily you can get a career in vfx will be very dependent on where you are located. If you're in Canada, England, India, China and a few other places you're likely to have an easier time than someone in the U.S. currently.   See Globalization and VFX for more info.]

[Here's another insight into the work place: Letter to the Animation Guild]

[Update: 11/19/2011 Worth reading: 7 Reasons You Don't Want To Work in the Video Game Industry - There is some overlap of Visual Effects and Video Games and some people move between the two.  Visual Effects isn't quite this bad but there are some sad similarities]

[Update 5/3/2012 I've posted What happened? that explains some of the facts of life in the visual effects industry. Check the comments as well.]

[Update 11/19/2012 Lesson in perspective is a note from a creative person in advertising. Same issues. ]

[Update: Most areas have now reached a saturation point of visual effects artists. That means it's becoming more and more difficult to not only get a job in visual effects but to keep it long enough to make it a career. All this in contrast to what some school recruiters and web sites may want you to believe.  It's important to understand what you're up against before you commit to a career in it and potentially spending a lot of time and money on specific education that may have limited usefulness outside visual effects and video games. Even though places like the UK are pushing for more students they too will become saturated shortly and the incentives there will not last forever.]


I've covered this not to scare you but to give you an idea of what the realities are. If you have a real desire for it, have some talent and are willing to work hard then you have a reasonable chance possibility of succeeding.

Education
When I started there were few film schools and certainly no effects classes. While in high school I shot Super-8 and 16mm film, was a newspaper photographer for the local paper and was a theater projectionist. Since film schools at that time required you to be a junior before doing any film work I opted to go from high school directly into visual effects. I was fortunate to find work as Doug Trumbull's assistant and to work on Close Encounters.

You don't have to have a college degree to work in this business and having a masters in film is not going to get you a job by itself. If you're planning to focus on the pure technical aspects such as computer programming a college degree will more likely be required. Many of the larger effects companies have Human Resource departments and they're the ones likely to put college requirements in job postings even though they're not required by the people who would actually be your boss.

Having said that there are certainly some advantages to going to college and getting a degree. If you have problems getting work in visual effects or wish to switch to a different line of work a college degree may be required for an alternate job. A good college should be exposing you to a wide range of ideas and experiences. I would suggest a college that has film and other liberal arts classes.

There are now a few specialized schools that offer visual effects and animation training. I don't have any direct experience with any of these.

The specific school is up to you but you might contact some of the effects houses and see if they have any preference. For a time a number of animators at ILM came from Sheridan College in Canada. Some effects companies send recruiters to specific schools but that's certainly not a guarantee. Be sure to check out information and opinions for the school as much as you can before you commit. If the school is near an effects company it may be possible to intern there or that someone may come to you school to speak.

[ Visual Effects School post]


While you're in a school (high school, college or tech school) take full advantage of it. You're unlikely to get the chance again once you graduate. Make friends and start networking with your fellow classmates. You never know who might call you at a later date with a job. Help out on a variety of film and video projects.

Don't limit yourself to only classes in your specific film area.
And please don't focus all your attention on one piece of software. There are no standard software packages that all companies use. A company may have their own in house software. It's important for you to understand the underlying principals and develop your eye. If you know the reasoning you can learn to use any software but if you only know how to push specific key commands then you're going to have a tough time. When ILM was doing Casper they were hiring 2D animators and training them to use the software. It's much faster and easier teaching someone to use a tool than to develop the artistic skills and underlying concepts.

Take art classes to get a better understanding of color, composition and developing your visual sense. You don't have to be an expert artist but you do want to be able to communicate ideas with sketches and doodles.
Make sure you cross train yourself.
Animators should take TD and composting classes if they offer them. TD's and compositors should take animation classes.
Take editing, writing, sound and other film classes. You're part of the filmmaking team and it's good to understand these related disciplines.
If you want to be an animator take acting and dance classes.
If you want to be a TD or compositor take photography and cinematography classes to understand how the real world appears. There are a lot of people entering this area who don't understand such things as depth of field or image compression caused by telephoto lenses. Since you're trying to recreate a virtual photoreal world or to augment a real world on film it's vital to understand these factors. Learn to really look at shadow from different sources. See how lighting and bounce light affect the image. Observe atmospheric haze.

Explore Theater classes. Set lighting is good for TDs. Set building may be worthwhile for modelers.

Team up with others in your class. If someone is a great modeler and someone else is a great animator you could work together to make demo material.

If your school has guest speaks from the film industry go to see them.

Chances are you school has video and film cameras so you can shoot some tests or shorts on them. They may have some advanced computer or editing systems that you can take advantage of.
As a student you also have access to a lot of software and computer hardware at education pricing which can be 1/3 or ½ of the retail price. Take advantage of this to learn and work with these packages.

Take some art and film history classes to get a frame of reference.

Self-Education
There are a number of other sources of information to explore whether you're in school or already working and want to cross train.

If you have a software read the manual it comes with and do the tutorials.

Publishers have a large selection of books covering specific packages to general techniques. Some good, some not so good so you should review it in a bookstore if you can. Does it provide real information and examples? I've posted a few I recommend in the effects corner store and I'll be adding to this. If you have any recommended books or other info you can post it on the effects corner website.

In addition to books on specific software packages there are plenty of DVD and even online learning available. Do an Internet search for material and reviews by users. Many feature films with effects have extras on their DVD's that you can rent or buy. Some provide more details than others. Some foreign films do a good job as well. The Japanese film Avalon had some nice behind the scenes.

For magazines there's similarities does a good job of covering visual effects.

Always take any of this information with a grain of salt. It's very easy to make even a process such as dirt removal sound very grandiose and new, especially in the world of sound bites.

Hands On
The fortunate thing about the current state of digital technology is that you can do it all at home reasonably easy. When I was in high school if I shot a stop motion animation test the film would have to be dropped off at the drug store and then I'd have to wait a week to see the results. 3 minutes of film without sound would cost $20. Today you can shoot an hour of MiniDV for $5. All visual effects had to be done in the camera when you're dealing with Super-8. Optical printing was not feasible for personal projects.
Yusei, a matte painter at ILM, learned how to machine to build his own Super-8 optical printer so he could do his own matte painting composites. So a MiniDV camera and even a simple home computer will provide a better starting point than previously available.

If you want to do compositing or matte painting get some hands on experience with Photoshop. If budget is an issue take a look at Gimp or other applications. Make sure to explore all the different composite modes, creating masks, blending and layering of images. If you have a digital still camera then go ahead and plan out a shot and shoot the pieces for it. Assemble it as a final still image. Does it look real? Does everything fit together as planned? Did you take into account the lighting of the background and foreground? By working on stills to start with you can focus on the actual final image and the process to create it.

Once you've done this a few times you now have a taste for some of the complexities involved in doing a real composite. You might have had to make some compromises or do a lot of hand paintwork to get it it finsihed. If you hand cut paths then you know how tricky this can be.

As Dave Stewart used to say "Now show me frame two." Dave was a motion control operator on Close Encounters who unfortunately passed away a few years ago. The point being that when you add motion the difficulty suddenly increases since you have to make 24 perfect images for every second of film.

If you have access to a MiniDV camera shoot some test footage. Experiment. Pick up a piece of green poster board at a craft store if you want to try green screen tests. Some people are locked into doing nothing until they have the ultimate system with the perfect camera. Don't wait, start doing. These are tests for you.

If you have access to compositing or 3D software go ahead and put it to the full test. Don't worry about making a full short, just try different scenes.

A note here: Please don't pirate software. People have worked long and hard to create it. The more a program is pirated the less it will be developed. And I'm sure you'll want to be paid for your own work.
As mentioned if you're still in a school of some type you can get an educational discount. Most software is available in a demo form that you can try out. Some, like Maya, are available as a downloadable learning edition.

On the job training
If you're not in a major effects center you might see if there are any related companies or jobs around. Anything to do with film or video would be useful. Look at working at a tv station or small post production company if one exists where you live.

As mentioned look into internships with effects companies. Be warned that some are more paperwork than hands on. These days most companies have a web site that has contact info as well as internships and job information.

{Update 5/3/2012 Be aware that some companies that are not totally legal or ethical may have you doing productive work for no pay. If you're in college then some intern jobs offer credits in return for interning. However if this is displacing someone that's a problem. And it's even more of a problem if you're paing for schooling and working for free. Internship issues. Paying to work.]

[Update 8/12/2014  Do you legally qualify as an intern and what are your rights as an intern?]

Company projects
Here's an average scenario for an effects company.
There's no work. Then there's a possible job. That goes away. Suddenly they get a greenlit picture and need to start immediately. They bring on the key people and the art dept. Now each area will be hired on as needed, usually in limited time windows. Modelers are hired early on but animators, TDs and compositors are brought on when the edited shots are going to be turned over. The project may continue with the staffed crew and then if a major crunch happens toward the end they may farm out some of the work or bring on additional crew for a short time.

Depending on the company they may not even be reviewing resumes and reels during the down time.

Most big effects films come out in the summer or Christmas time and take anywhere from 6 months to 2 years in total. The summer is usually the slowest for getting projects started and hiring people.

Hiring practices
Employment in the visual effects industry goes something like this:

When a company has a project they will employee the people that already work there first. Next on the list will be people who have worked there but had been laid off or temporarily working elsewhere.
The next level recruited will be people from outside the company who are recommended (and have worked with) by someone on the current crew.
Next on the list will be people with credits and experience on feature films.
Last on the list will be the people with no experience.

Companies know that most people without hands on experience are going to need some additional hand holding and possibly training. Note that even those employees who have come from other places will need some training to learn the systems and possibly any specialized software used at the new company.

If two inexperienced people are up for the same job and are similar in other qualities, they will give the job to the person that knows their software (assuming it's not proprietary software)

Applying for a job
Check the company website to see what jobs are currently available and what their requirements are. If you don't quite match the qualifications or if your job isn't listed you can still submit an application just note this on the cover sheet. Large companies will have a human resource department or possibly a department manger that will do the initial review.

You can apply to multiple companies at the same time. You might as well start with the biggest ones rather than submitting only to small or obscure companies.
Keep track of when you sent it and who, if anyone, you spoke to. You can follow-up with them if you haven't heard in a few weeks. Some companies will have a ‘we'll call you if interested' policy since they receive so many applications.

Many companies recruit at SIGGRAPH and other conferences. SIGGRAPH is a computer graphic conference held once a year in a different city. There are also large animation conferences around the world. Check on the company web sites and see if they will be recruiting. They may require you to signup or submit your resume and reel before the show since they will have a limited time to interview people. Recent Visitor Activity

[Update 5/3/2012  The Visual Effects Society (VES) now has a yearly career fair that is held in major visual effects centers around the world. Be sure to check this out since it's specific to visual effects.]


Don't contact a supervisor or crewmember that you don't know. If they don't know you it's unlikely they'll make a recommendation. Also note that most of the crew is either 1. Not working 2. Shooting on location 3. Very busy so your submission may end sitting on a desk for months. Better to get it to the actual people doing the hiring.

The main things you will need to provide are a resume and a demo reel.
Your resume should be focused on any and all applicable work experience you've had. If you've worked on any productions be sure to list these credits. Be clear about what it is (student film, feature currently in production, etc) and what you did (compositing, PA, etc) Your work experience and credits are more important to these people so cover that first before your education. You want to make everything sound good but do not lie on your resume. This will bite you at some point in the future. If you say you know specific software and don't then they will find out even sooner.

[Update 5/3/2012  Please read about getting a Deal memo with the company who is hiring you. You don't want to move across country or to another country only to find out it's not what you thought.]


Demo reels
If you're an experienced effects artist with a list of credits a demo reel probably isn't necessary but if you're inexperienced this can be more important than your resume. This demonstrates to them several things. The range of work you've done, the complexity of the shots you've worked on, and the quality of your work.
Hopefully you've been working on some great pieces while in school and working on your own.

There are no standards for reels so I'll just run through some of my own preferences.
Check the company web site to see if they have any specifics for demo reels. These days they're on DVDs and usually 3 to 5 minutes in length. Put only your best work on the reel. It's better to have 3 great minutes than 5 minutes padded with poor shots.

Be honest. Would these shots hold up in a feature film or TV commercial? If they aren't then your odds of getting hired are much lower since you'll be competing against people who do have polished work.

You don't need to create a short as your demo reel. If you've already done a short that has won a number of awards then you might consider including it or a snippet of it but don't bother writing and completed a full short just for the purposes of a visual effects demo reel. It may be a little bit more appropriate for animation but take a hard look at it.

When you create a short you're going to be spending a lot of time, money and effort on things unrelated to what you're applying for, which is visual effects. A short will end up being judged to some extent on how good the short is, how well the music works, etc. You're unlikely to show a range of different techniques or processes in one short and more likely to be showing a number non-effects scenes. If it's animation then you'll only be showing one style of animation.

Put that same amount of time and effort into different shots that show case your work.

Avoid using tutorials, no matter what their source. A tutorial just shows that you were able to complete something with the help of a teacher or book. When a company hires you they expect a professional who can figure out what steps are needed to do to finish the shot. You also want your work to stand out but if 30 other people from a class submit a demo with the same tutorial it doesn't make a good impression.

Try editing your shots to determine what shows off your work the best. You might want to show the finished shot and then the original image and then back to the finished shot. This is showing the before and after so it's clear what you changed or added. If it's a complex shot you could quickly show the build up of each element. Look at some of the behind the scene DVD's to get a sense for this. Don't spend the entire DVD breaking down one shot. The point here is to show the complexity and finished quality of a number of shots, not to teach them.
Include one to three seconds of black between sections. You can include a shot or two before and after if it is from a larger project and if it's relevant to the visual effects shot.
Don't turn on auto-run for the DVD and don't have motion menu that shows them the demo in a thumbnail. You want them to see it at full quality all at once.
Don't go fancy with the titles and transitions on the DVD. Keep it simple.
You don't need to run your name at the bottom of the DVD image. You don't have operators standing by and the potential employer doesn't have a limited time to call in. Just a simple start menu with your name and contact info is fine.
Include your name and contact info on the DVD case and the DVD insert as well as your resume.

If you have long segments consider putting chapter markers and or an index so they can jump ahead.

I suggest printing on 5 x7 paper for the DVD inside insert. List the shots that will be shown and list what you did on each. You want to be clear about what role was on each shot.

Sound track – Many people watching will turn off the sound but sound does play an important roll when viewing visuals. Keep it simple. Avoid things like electronic trance or heavy metal since that quickly becomes grating when watching dozens of demo reels. Likewise don't put them to sleep with very slow classical or new age music. Keep the music level down, especially if you have sound effects.

You can use a permanent marker to write your contact info on the DVD cover and the DVD itself. If you have the option you might consider printing the cover label to make it a bit cleaner. They sell DVD cover in matte and glossy finish for inkjets. The DVD can also be printed on if you have a printer that can do this. Watch out for stick on labels since they can cause problems playing the disk.

Don't bother doing a full mass produced disk. You probably have access to a computer than can burn DVDs. Check each one before sending it out and put it in a bubble pack for shipping. Don't use the paper filled padded envelops.

Don't get fancy with the final package. A hand carved wood case isn't going to mean anything if the content of the reel is poor.

Well that concludes this weeks Effects Corner podcast. There may be some delays with the next few podcasts with the holidays.

As always this podcast is copyright by Scott Squires 2005

Another reference: Demo reel notes from vfxhack
Making a Demo Reel that Doesn't suck

And Digital Tutors has a helpful page on making visual effects demo reels.
Making a Demo Digital Tutors Demo Reel help

Making Demo Reels for technical directors and riggers tips
Rigging Demo Reel tips


Additional Notes-
For printable DVD (Not required but certainly nice looking)
Epson R200 Printer
Epson R220 Printer
Epson R300 Printer
Epson R320 Printer

Latest which is relatively inexpensive and much improved DVD transport
Epson Artisan 50 Color Inkjet Printer (C11CA45201)

[Just a heads up for those with Mac 10.5 or newer. Epson seems to have a hard time updating their print drivers and their tech support is very poor so make sure whatever printer you select runs on your system and can print to DVDs]

Printable DVD's
Avoid Memorex since they have their name printed on them.
Ridek have the nicest printing surface.
Fuji is fine in a pinch (available from some local camera stores)
Discmakers Premium have the smoothest edges but aren't as opaque

Latest:
Taiyo Yuden WaterShield - 50 x DVD-R - 4.7 GB 16x - white - ink jet printable surface - spindle - storage media


Check the disc order. Since some of these come with no spindle order a cake box for the discs or you're likely to see them spill over your floor. Dirty discs aren't great for burning.

If you plan to print photos on the cover of your DVD case get Meritline Photo Gloss DVD case inserts. Avoid Memorex- printing quality and look is substandard for any photos.

Related posts:

Visual Effects Positions

Getting  A Visual Effects Job
What to do when you're laid off

 What makes a good visual effects artist?
 Visual Effects union, Tk 2

Other site:
Why is the VFX business failing at its moment of greatest success?
Tom Cruise info on schools, companies and software for vfx


Wednesday, December 07, 2005

Questions for Listeners

Now that I've posted a few podcasts I thought I'd check to see how well it's working for listeners.

Do you stop by these pages much? I publish occasional non-podcast material (such as this) and wanted to see if it was worthwhile.

How are the length of the podcasts? Is 30 minutes too long?

Index-
I listed the times for the sections in the last podcast. Did you notice this in the description of your podcast application? Was this useful?
I can add actual chapter markers for ipods/itunes but this is an Apple format that's not readable by most other devices. I'd rather not post 2 versions.

I reduced the bit rate of the last podcast so it's less than 1/2 the file size. This should make it easier to fiton devices and faster to download. Is the quality still ok?

Thanks.

Tuesday, December 06, 2005

PostProduction

PostProduction for Visual Effects is covered in this podcast.

Here's the timeline:
2:10 Client turnovers
6:24 Effects editorial
8:41 Scanning
12:08 Effects turnovers
15:21 Artists - Matchmover, Animator, TD, Compositor, Rotoscoper, Painter, CG Modeler
19:10 Work day
22:17 Dailies
24:34 Client reviews
26;33 Temp screenings
28:09 Balancing work and schedule
29:36 Filmmaker

Transcript
Today I'll be discussing Post-Production for Visual Effects. This will be an overview with later podcasts to cover each specific area in more detail.

As with all of these podcasts I'm providing information based on my experience. Every effects house and film will be slightly different so use this as a starting point.

Effects Pre-Production
By the time the actual work is to start on the visual effects most of the CG models that will be animated will have been built, chained and painted. The various pipelines should already be set up. A pipeline is the workflow and the support for that workflow with specific tools. A shot may be passed assembly line style from one person to another. It may also be worked on by more than one person at the same time. The images and the data is passed from one software package to another. Animation may have to be done in one piece of software and then exported to be lit in another piece of software and then rendered using yet a different software. Creatures with fur may have to go through a different render pipeline than non-furred creatures. The output images are then composited in yet another piece of software. The idea is to make this transfer of data as easy and seamless as possible. This may involve writing special databases and scripts to help move the data and keep track of it. If this is an established effects company most of this may already be in place but there always seems to be some changes required. The CG supervisor is usually working on this pipeline while the film is being shot.

If there is an animated CG creature most of the voice recordings are also done by this point.

Client Turnovers
The first step of the postproduction process is the client turnover.
When a sequence has been edited the director, editor and producer turn over the visual effects shots to the effects company. The effects company team includes the effects supervisor, animation supervisor, effects producer and typically an effects coordinator. Everyone gathers around the editing machine, usually an Avid, while the director explains what's required in each shot. A 10-minute sequence in the film can easily take 2 hours to review and discuss due to the complexities of the shots and action.

Even though the effects shots have been storyboarded in pre-production there are always additional details now that the background plates have been shot. There are always some changes as well in the shooting and editing process. A single planned shot may have been broken into to 2 shots or two shots may have been combined into one big shot. In some cases shots have been dropped for pacing reasons and a few may have been added to help the story telling.

Depending on the shot it may be difficult to make the edits, especially for a shot where most of the scene will be added later. If a shot will be all virtual as a standalone miniature shot or a CG virtual shot then they will be cutting in a storyboard or an animatic to use as temp placeholder for the real shot to come later. They may have cut in the reference take so they can see how the action flows but they will have selected their real take based on the actors performance. In other cases they want to use a reference take and you'll need to remove the other actor or monster stick.

One thing I try to do when possible is to create mockups before the edit. I did this quite a bit on Van Helsing. A QuickTime of a shot would be copied to my iPod while we were shooting and then I'd tried to do a basic mockup at night back at the hotel and dump it back out. This tended to be mainly 2D mockups but was enough for them to check the take and get a sense for the action. It also allowed me to see how well something was working and to determine if we may have to make adjustments in the future.

The editor or his assistant may do simple mockups on their editing system. A shot may be split or a simple bluescreen key may be done. If animatics are generated it's sometimes useful to do a render of just the foreground or background. If it's a background this can be comped behind a bluescreen and if it's a foreground piece this can be comped over the real background. All of this is done to provide a better sense for which take and timings work best. In some cases they may pick alternate takes if there's a problem later with animation timing.

Since each shot is covered in great detail with much finger pointing at the video screen and pantomiming by the director we usually video tape these sessions in addition to taking notes. It's important during these sessions to get as much information and detail as possible since any miscues could be costly in time and money.

Since the number of visual effects shots these days is going up and the amount of postproduction time is getting shorter it's very common to do these turnovers while the film is still being shot. This is usually spelled out in the contract since the film has a fixed release date. The delivery date for all the shots to be completed by the effects company is called the finals date and can be 2 weeks to 2 months before the release of the film. The editor will start making an assembly from the dailies and the director will review this after a day of shooting or on the weekends. Once the director is happy with a full sequence the turnover will happen at the end of a shooting day or on a weekend as well.


Effects Editorial
Once the client turnover is done the show's editorial department usually ships a copy of the edited sequence. This may be on a tape but ideally is in Avid project or some means for us to assemble our own edited version. It's important to have not just the visual effects shots but the surrounding live action shots as well. This will allow checking the in-progress effects shots in context so we can check the timing, actions and the match.

The effects editor creates a breakdown, line up or cross over sheet. This will list the sections of film that need to be scanned and any additional elements required. The standard references of the lighting sphere and other items are some of the additional elements. The effects or animation supervisor may want to scan additional reference footage.

The editor has the option of extending a live action shot at any point because there's usually plenty of additional footage on the head and tail of the selected cut. With visual effects though you end up with a shot just as long as specified. To provide a little latitude for offsetting or increasing the shot length an effects shot usually includes additional frames at the head and tail of the shot. These extra frames are known as the handle. This could be 2 frames at each end or up to 16 frames at each end.

The more frames you have, the more flexibility in the edit to make an adjustment but these added frames add an additional cost to each and every shot. 16 frames of handle would mean a total of 32 frames of extra work that likely won't be used. That's a second and a half. That's a lot since the typical effects shot is 5 to 8 seconds in length. A 4-frame handle is probably most typical. The average shot length and required handles is spelled out in any effects contract. The size of the handle can be discussed on a shot by shot basis since in some cases the extra frames may require a lot of paint out or other work.

Scanning
Once the information is together and the original negative is available it's scanned into the computer. Some effects houses do this themselves and others send this out to a service to be done. Normally I try to obtain timing clips from the DP (director of photography) so we can do some basic color balance when scanning. A timing clip is a few frames of a shot or shots that the DP has worked with the lab to create and is an example of the color and brightness for the final shots. This shows the DP's vision of what the end result should look like. Some places wait until the end of the process to do a full color balance.

Scans are usually specified by their resolution, bit depth and format.
There are a number of formats and possible aspect ratios when shooting: 1:85, 2:35 anamorphic, Super 35, etc. It's normal to try to scan a bit more of the frame if it exists such as in 1:85 on the top and bottom (and one side if it's academy format) This allows a bit more room to move the clips.

Typical resolution for feature films is approx 2k or 2048 pixels across. Some films are being done at 4k or 4096 pixels across but that requires 4 times the amount of data and processing. The bit depth refers to how many levels of lumance for each color. 8 bits is 256 levels and provides over 16 million colors for red, green and blue. 10 bits or higher is now more common since it provides finer increments of color. It's also important that these scans be logarithmic to provide the best use of those bits. Some people think films have to be more than 2k and have deep color but the fact is quite a few well known films were done with 8-bit and less than 2k resolution. The file formats are usually in a Cineon format but there are many others, especially for in house scanning.

High-resolution images take up a huge amount of storage space. Even a simple 8-bit, 2k image will take 10 megabytes per frame. Since film runs at 24 frames per second and since there are usually multiple film elements per shot that starts adding up quickly. When possible images are sometimes compressed in a lossless compression. This will reduce the amount of storage required and reduce the amount of data to be copied between computers. These scanned shots are dumped to a high-density data tape or across a network.
Even though effects houses may have terabytes worth of storage shots are usually brought online (loaded on to hard drives) when the shot is about to start and they're normally removed as soon as the shot is finaled.

After a shot is scanned it typically goes through dirt removal. A team of people sit at computer workstations looking for dirt and scratches that have to be painted out, typically by hand, before the shots are ready for production.

Effects Turnovers
When a few shots have been scanned and are ready to be worked on there are turnovers for the actual people working on the shots. A shot usually goes through a number of departments, some of which work simultaneously on the shot and other departments that may have to wait until the previous department finishes. A single turnover may happen with all the key people who will be working on the shot or it may be broken into multiple turnovers for each department.

The shot will be displayed on a computer or video monitor and the animation or effects supervisor will step through the key issues much as the director did. It's important for all those in the turnover meetings to have a pen and paper for notes. This would seem obvious but a lot people try to remember every detail only to find out they forgot something a week later.

In some cases a section of video of the director turnover may be shown just to make sure there's no miscommunication.

Every shot and every element will have an ID of some type. Possibly the first 3 characters of a sequence name followed by the shot number and then possibly a letter or letters signifying the element itself. All this is written up by editorial and provided to the people working on the shot. Larger houses also have a database with info and access related to each shot. This is critical since one of the bigger tasks in doing visual effects is keeping track of all the pieces.

A single shot can take one person a few hours or can take a number of people in 6 departments a few months to complete. A few linear weeks are probably typical with it being touched by 5 or 6 people. Most people are assigned 2 or 3 shots so they can continue to work even while waiting for feedback or additional elements on one of their shots. Each person is assigned a basic schedule and deadline for their portion of the work.

For a large sequence in the film there may be a sequence lead for technical directing and a lead for animation. The lead TD will establish the basic lighting for the sequence based on the live action and will act as mentor to the other td's and compositors working on the shots in that sequence. They'll also be involved with specific R&D required for a sequence. The animation lead will try to establish the basic character action for the sequence and help to mentor the other animators as required.

A show could have a dozen people but more than likely will have 50 to 300 people working on it. A large effects house may have 2 to 5 shows going on at one time. It's important that schedules and plans are laid out and that sequence leaders be able to manage their team. These crews are made up of true artists that are at the core of the effects work you see. They have a balance of artistry and craftsmanship.

Some of these artists include:

MatchMover
A matchmover is provided with information about what's critical in the shot and what's not critical. In some cases a rough matchmove is requested first so it can be passed on to the animator to get started on. The match mover is provided with measurements, photos and additional information from the set for a specific shot.
Once the matchmove is done a grid or spheres are rendered as an overlay with the background to check the work.


Animator
The animator on the shot will take the matchmove and start roughing out the animation. Ideally the sequence lead animator may block out or rough in the animation over a sequence of shots. A low res single color plastic render will be created for each shot. This is overlayed with the background plates and cut into the sequence. Once this is done it is sent to the editor and director for review.

Technical Director
The Technical Director or TD is the person that does the lighting and rendering of the CG creature or model. The also deal with any 3D technical issues on a shot. On the credits they're usually listed as Digital Artists since the Directors Guild controls anyone who get's a director credit of any type.
The TD can start the lighting as soon as he or she receives the first animation from the animator.

Compositor
The compositor is the person who handles the 2D work including compositing or combining all the different pieces of film or elements, including computer generated elements. They start their work prepping the different images, requesting paint and roto work as need be and then take any rendered CG images from the TD. The compositor adjusts the edges and color balance of each element to make sure they blend seamlessly.

Rotoscoper
The roto person creates hand drawn mattes as needed. If a shot has a CG creature run behind a table someone has to draw the outline of the table and create a high contrast matte that will be used to place the image of the table over the image of the creature. In the case of something like Dragonheart the actor in the foreground has to be rotoscoped while moving so we can place the dragon behind them.

Painter
The painter goes through at the start and paints out any special rigs or other items that shouldn't be in the shot. They try to use the clean plate if it exists.
When a shot is finished it may require some slight touchup on a few frames where the render or composite wasn't quite right. There's much more handwork involved in doing visual effects shots than most people realize.

CG Modeler
Actually modeling usually involves a number of people. People who do the model, others who paint the texture maps and others to build the shapes, skin and skeletons for animation purposes. Hopefully this has been done but additional model shapes may be required, especially for facial animation, while the shots are being worked on.

Some of these tasks such as TD and compositor may be combined into one artist. It's possible for a single person to do most of the shot themselves but this may not always be the most efficient.

Work Day
Once the shot has been turned over each individual goes back to their workstation to work on the shot. As they progress they let other's know there is an update. In many cases they may check their work into a database. This is similar to software development where files can be checked in and out.

When an animator is going to do additional work it's important for them to have the latest version of the matchmove. Likewise it's important for the TD to have the latest animation to light and render.

In the old days you had to finish any work by the end of the day (such as opticals or motion control) to get the film into the lab. In the digital age you try to get everything done before the end of the day as well so the computers can render over night.

The TD may be checking single frame renders during the day as he or she makes adjustments to the lighting. The animator will be looking at wire frames or plastic renders to check animation and the compositor is working on a few key frames to make adjustments.

One of the things that these people also do during the day is to calculate the amount of computing power required. If you have a 300 frame shot and each frame will be taking 1 machine hour to render that needs to be taken into account. A large effects house will have a render farm made up of the individual machines as well as a cluster of specialized rendering computers. A single shot can be spread over multiple computers over the network. A frame could be sub-divided in to multiple sections to be rendered or each frame can be passed to a different computer. There may be dozens of shots being rendered overnight.

Everyone that needs rendering usually logs their request into a database and the CG supervisor will have to review the requests versus amount of computing available and determine how the work will be done. Some of the overnight work is done at lower resolution so animation and basic rendering can be checked without using up too much computing power. If it's a final render then it will have to be a full resolution with motion blur and fur rendering and anything else. These types of renders may take a few days and could be scheduled to run on the weekends.

Additional elements
In preproduction and during filming a list is made of other specific elements that need to be filmed. These could be smoke from chimneys, fire for a building or water splashes that have to match a creature jumping into the water. During the compositing process a few more elements may be found to be necessary to finish the look of the shot. These will have to be filmed and scanned before the compositor can complete the shot. Ideally the effects company has past footage and generic elements for at least some of this.

Dailies
On every show the dailies are handled a bit different. The number of shots and the length of time to review and comment can make it very time consuming.

In the morning the effects supervisor and animation supervisor may meet and quickly review the shots together in private. If the animation supervisor has any comments about rendering, compositing and lighting issues he or she would make it here and visa versa.

Dailies can be held in a large theater with high hres video projection with the entire crew or could be in a smaller room with just the sequence people or could just be a one on one review of the work with the supervisor and the artist. All of this is a balancing act between making sure the artists get feedback on their own work as well as seeing the related work and at the same time avoiding tying them up for all morning sitting and watching dailies.

Animation and TD/Compositing dailies are usually separate. Hopefully the effects editor has already cut the dailies into the edit so it's possible to review the shot in context.

I usually try to review the shots on my machine before dailies so I have some notes and can quickly cover a lot of issues. Some people want to wait for a review until they've fine-tuned their shots but this may mean a week until any progress is seen. If for some reason there's a mistake or miscommunication while the artist is polishing the shot then all that work will have to be re-done.

As with the turnovers all artists should bring a pen and pad of paper to take careful notes during dailies. When possible the TD and compositor should explain what they've done and what they still have yet to do. Because of time constraints most of the focus will be on work that still has to be done or improved rather than praising the artist for sections that have been completed.
During the course of the day the supervisors may check in with the artist or may get email from an artist requesting a review or a question.

Usually there is a coordinator assigned to each supervisor. They help to follow-up with the artists and track down information as needed.

Reviews
Because of the complexities and time of doing visual effects it's critical to make sure to frequently review the shots in context. Some people try to wait until they're finished with the shot but there's a strong likelyhood the director will want to change something and they may not be able to make a critical decision until they see the surrounding shots. Each director has a different ability to visualize the shots. Some have difficulty in viewing plastic renders and making animation decisions based on these. This is a learning process for working with each director.

Once or twice a week the supervisor will determine which shots to show the client. These may be shots in progress where a confirmation is requested, or shots where a question has come up or a shot, which is considered a final by the supervisor. Usually there's an animation final on a shot and then later a TD/compositing final. The supervisor will go to the editing room to show the director and editor the new work. If the director is in another city a DVD may be sent or a live video link is used. The latter is much preferred. The video link allows the artists to be present and hear the comments right from the director.

It's still possible for changes to be made at any point. If changes are outside the scope of the original budget for the shot then a change order may be called for where a new or updated budget is submitted for approval.

Once the shot has finaled on video by the director it needs to be rendered full res if it hasn't already been and then be filmed out. The director views this film projected on a full size screen to determine if it's a final final. When a shot is finaled a few frames are saved at full res for PR purposes and the final shot and key elements are backed up and removed from the server.

Temp screenings
The director probably has to show the film to the studio a few times during the course of postproduction. Of course the director will want as many of the shots done or in at least some form of completion even it's with temporary shots. This is better than showing an actor sword fighting with a ping pong ball on a stick or actors on a bluescreen pointing to a non-existent object.

These temps are also used to help the composer and sound effects people since this work will be ongoing even while the visual effects work is still in progress.

As the film gets closer to release it becomes important for the studio to do test screenings. Unfortunately test audiences don't have too much tolerance for plastic renders of dinosaurs and other temporary shots. If the test screening is a wild success the studio may authorize more effects shots. If a test screening does poorly they may want to rethink and redesign some of the effects shots.

Trailers
The director and marketing people select shots that they think would be good in a trailer. A trailer being the ad for the film shown in theaters and on TV. Unfortunately they sometimes select shots that aren't even scheduled to start for several months. As a result trailer shots can be rushed and the version for the final film will be noticeably better. It's best not to judge the effects work too much based on the trailer.

Balancing
For those of us working in visual effects it becomes very easy to fixate on every detail in a shot. This is especially true since we can change everything in a shot. We loop the footage over and over on a computer monitor or large screen at full magnification. We know where to look so it's easy to spot any imperfections. We have to remind ourselves if we don't spot something in 2 or 3 times through then the shot's done.

The same problem holds true with the directors as well. If they film a jet fighter flying by for real then they will select a take and move on. If it's a motion control model or a CG model then the director usually gets caught up in making the jet roll a specific amount at a specific frame even if the original take matched the live action version. Just because there is infinite control doesn't mean there should be an infinite number of takes.

All this is important because in order to generate hundreds of effects shots in a given amount of time you have to keep moving ahead. If you spend half the postproduction time on a fourth of the shots then the other shots will be rushed and the quality level will drop. It's important to develop a pace that can be maintained during the production or you'll end up working long weeks and hours the closer you get to your finals deadline.

Filmmaker
If you're doing your own film and even all of visual effects there's still some principles to apply.

Before you begin the full postproduction process make sure you have your pipeline working. It's better to work out the kinks before you have 30 shots and a looming deadline. Run a short test shot from your editing software to your 3D software to your compositing software and then back to the editor. Use your manual and online help to make sure you understand the different steps involved.

If this is video, export from your editing software with some additional handles. Keep a log book of the shots including timecode and other information. Avoid re-render and recompressing when possible and use lossless compression such as the QT animation codec if you plan to manipulate the images through more than one software system.

Find out the required field order. Most video footage, especially DV is set for lower field. If this is 24p video make sure you understand how to remove and how to add pulldown. Some effects composting software can do this but you may want to do the pulldown removal in the editor if you plan to use multiple programs.

Do test sections and frames and set your programs to render overnight for rendering if you can.

If you're having other people help with the shots then do a turnover with them and be clear about what you need. Figure out a naming convention and how you plan to pass images back and forth. Firewire drive, networking, etc.

Try to keep an honest assessment of your work and the time required. Is the quality up to the level you need? Can you finish all the shots in the time you have? Use a schedule to help keep track of your time and your target.

Try to rough in the animation or basic composites for a sequence so you can be sure it's working in your film before you spend a lot of time fine tuning the shots.

Sunday, November 27, 2005

Moving Camera

Using a moving camera when filming live action for Visual Effects.
Locked off camera, Post Moves, Motion Control, 2D Motion Tracking, 3D Match Moving and Face Markers are all covered in this podcast relative to live action photography.
Approx 25 minutes.

Transcript
Today I'll be discussing the moving camera.

Locked Off
The simplest type of camera move is no move or the locked off shot. The camera is placed on a tripod or dolly and isn't moved. This makes it easier to add visual effects later or to do multiple elements of the same setup. Examples of this could include adding a matte painted house to the top of a hill. If you wanted to create a shot where part of the actor is removed later – such as a leg as in Forest Gump or most of the body as in the invisible man you would shoot the shot two times. Once with the actor and another time with no actors. This shot with out the actors is called a clean plate and is pretty common for many visual effects. Because the camera doesn't move you have identical images – one with the actor and one without. In post production if we remove part of the image of the actor the clean version gives the image without the actor. Special rigs are removed the same way. This same process is easily used for creating twins from one actor. Shoot the scene once with the actor on the left side and then shoot the same thing with the actor on the right side. Because these shots don't change position you can do a simple split down the middle of the scene.

Normally the camera operator is making slight pan and tilt adjustments while sitting on the dolly and the asst cameraman is making slight focus and exposure adjustments. To obtain the best quality of clean plate get everyone away from the camera, off the dolly and avoid changing the settings, even to do slates. The size and position in frame will be different if anything changes, including the exposure. You can spend time fixing this in post but it's better if you can avoid the problem.

Even though a locked off camera makes it easier to accomplish visual effects it may not fit with the look of the rest of the film or the requirements of the shot.

Post Move
Doing a move on an image in post is sometimes called Pan and Scan. This also can refer to transferring a widescreen film to full frame video.

The scene is photographed normally and then in the composite stage the image is enlarged and a synthetic move is added by moving the image digitally. It's also possible to do this type of move with some scanners for better quality.

The problem here is the loss of resolution from enlarging the image. If your end production is video then it's possible to scan the film at a higher resolution.

In the past another way around the resolution problem was to shoot on VistaVision or 65mm cameras. VistaVision a format which shoots with special cameras that run 35mm motion picture film sideways, much like a still film camera. This larger film size allowed for blowing up without as much quality loss in the days of optical printing. Large formats were also common when doing any effects heavy productions in the days of optical compositing. 2001 A Space Odyssey, Close Encounters and Blade Runner are some of the films that used 65mm. Star Wars and most ILM films used VistaVision for effects until the last few years

If the live action element only makes up a portion of the frame then a post move doesn't cause a quality loss. An example of this is starting on a scene which is all live action and then pulling back to reveal a large matte painting extension to the scene. In the old days a motion controlled camera might be used to film a physical matte painting on glass. A rear-projector would be one method of adding the live action with the same move. With the advent of digital matte painting the matte painter creates the painting at a higher resolution. If the original live action scan is 2000 pixels across, the matte painting might be done at 4000 pixels across if the final scene was going to show twice as wide.

I'll discuss 2D match-moving later in this podcast, which is a form of post move on an element.

One of the problems with post moves is the very limited 2D or two-dimensional appearance of the moves. There's no perspective change or feeling of depth. To obtain true 3D camera moves of the original live action there are a couple of processes.

Motion Control
One way to deal with this is using motion control. Motion control is used frequently with shooting miniatures and models but here I'll focus on live action use. Normally the camera is mounted on a pan and tilt mechanism known as a camera head. The operator has a hand wheel for pan and one for tilt. For motion control you have a special head and usually a special dolly where all of these motions are controlled by motors. In some cases the operator moves this just like a regular head and a computer records the positions by using position encoders. In other systems the operator uses a joystick or a remote camera head that is designed to just record his hand moves. In this case the remote head looks like a camera head but it's just a box with the hand wheels.

Note that non-recording remote camera heads are also with live action frequently when the operator can't be at the camera itself. The camera is on a boom arm or other remote system where the operator watches a video monitor and remotely controls the camera.

With true motion control once a camera move has been programmed the move may be repeated over and over again exactly in sync with the camera. The repeatability means you can shoot the same actor walking through the scene multiple times with a complex camera move. This would be done to create twins using one actor during a camera move. Motion control also allows you to film moving clean plates so you have many of the same benefits as a locked off camera such as rig or actor removal. Since the move is recorded you can also take this data and use it later in a motion control system for models or convert the data and use it in the computer for adding CG elements.

Motion control can also be used to shoot secondary elements such as bluescreens people or objects that exactly match a previous live action plate. In this case the data for the move comes from the original motion control shoot or from a process called match moving, which I'll be covering shortly.

The downside of motion control is the requirement for a special system that has to be setup and be programmed. Most directors hate it because of the extra time and process. I recommend it only when you really have to get repeatable motion on the set or location.

I'll cover more details of motion control in a future podcast.

MatchMoving
The other option when a moving camera is required is to do matchmoving in postproduction. This is now one of the most common techniques that came about with the advent of the computer. The simplest technique is shot with just a pan and tilt that requires another images to be added later in the composite. As an example if we pan and tilt an outdoor scene and wish to put the image of a flying saucer hovering we could matchmove a point near the horizon or infinity like a distant mountain or building.

This is done after the film images have been scanned into the computer. These days' most professional compositing programs allow you to specify an area in the moving footage that you want to track. Frame by frame the computer compares the image in this area and tries to find the best fit around where it was last. We call this 2D tracking since it's only calculated in 2 dimensions x and y.

Once this is done the image of the flying saucer is composited over the background and the motion of the background is applied to it. Now you have a scene with a pan and tilt of a cityscape and a flying saucer that hovers over a building no mater what move you make. This creates the illusion it was there the time of photography. If you have 2 distant points that you can track then it's possible for the computer to calculate the rotation and size so you can not only pan and tilt but roll the camera and even do some basic dolly or zoom moves. I suggest distant points to track so you can obtain a more accurate motion track without having to worry about parallax or perspective. You typically also want to track a point in the scene close to where you want to place the additional image. Make sure you always have at least one or 2 points in the scene to track during the entire scene. If you're doing a big pan move make sure there's another suitable point that you can switch the motion tracking to during the shot. Ideally these would be close to the same distance away from camera.

Even though this is a 2D track it's possible to obtain 3D pan and tilt information. By knowing the lens used to photograph the scene the computer can calculate and output a 3D camera file that can then be used in 3D program for the 3D camera to pan and tilt. This renders an object that matches the move exactly.

Another variation on the 2D tracker is a 4-corner track. If you have a billboard in a moving shot and want to replace it with a different image you could track each corner of billboard on the computer and tell it to apply the move to each corresponding corner of the new image. This will distort the new image to fit it in the billboard even if the original scene is moving.

3D matchmoving
The next level of match moving is 3D match moving.
When shooting a scene measurements are taken of any landmarks in the scene (windows, doors, tables, that sort of thing) and in some cases special markers are placed in the scene. Later after the film has been scanned into the computer a person called a matchmover will build a rough replica of the set or location in the computer. The virtual camera, which is a simulated camera in the computer graphics program, is now animated to match the move of the film camera that filmed the live action scene. Originally this was done as a manual process of lining up the CG set with the image from the film. Now much of it is done using special 3D motion tracking software.

Note that some measurements such as the focal length of the lens may be a bit different than marked. If it's labeled as a 50mm lens it could in fact be a 48mm or a 55mm lens. As such you may need to make some adjustments manually to get the final matchmove perfect. Also be sure to check any automated 3D matchmoves since it's possible to fool the computer.

Now that we have a CG camera that matches we can now place a CG object such as a box on the match move floor and it will look like it was on the floor in the original photography. It still has to be lit and composited into the scene but it stays locked with the correct position and perspective in the scene even if the camera operator is moving a hand held camera around the imaginary object.

If a CG creature will be walking on rough terrain hopefully the matchmover has been able to recreate that so the animator can always keep the creature on the ground. This terrain shape is likewise used to cast CG shadows onto. The matchmover has also included any large objects such as tables and trees so the animator can avoid those when moving his creature. If the actor in the scene is interacting with the creature then the matchmover moves a CG pawn that represents the actor. In some cases the matchmover has to do a very tight match of the arms and legs of the actor so the animator can time and match the creature to the actor. Even though I'm using the term creature this could be any 3D object or effect such as CG sparks.

So now that we have the basic of the matchmove process down lets take a look at how that works when we shoot. If you're going to be using 2D tracking then survey the scene and make sure you have some definable points. Any place of sharp contrast or a spot. The corner of a building against the sky provides a clearly defined area that is fixed. The edge of a tree blowing in the wind is not a good point since it's changing. The edge of a building isn't a good point because it needs to be one specific and unique point.

These same requirements apply to four-corner tracking. If you're replacing the image of an old TV you may find that the TV screen is rounded and almost blends into the frame of the TV. In this case you may want to put fluorescent dots from the office supply store on the corners of the area you want to track. You'll need to paint or composite out the dots in the final scene.

If tracking points don't exist in the scene and you need them then you have to create them. If you're shooting an actor in front of a blue screen to create a distant vista in post production then place markers on or in front of the bluescreen. These may be 2 to 6 inch plus marks made out of tape or plastic. If it's a cloth screen material you can put Velcro on the back of the plastic markers. If you can't touch the screen use c-stands to hold them but note that there will be more removal work to do in post. It's important for any markers to be solidly locked down so don't suspend with them with thin wires.

You want the markers to be visible on the final film scans but not too large or you'll be doing a lot of extra paint out. Same with the number of markers. You want to always have 2 or 3 markers visible even when you pan and tilt the camera. If you plan to pan the camera 180 degrees hen you'll need a number of markers around the camera. The actors or props may obscure some of the markers. If you're doing a full day of shooting in front of the bluescreen then it's best to just setup a grid pattern of the plus marks. Note that if the depth of field makes the markers way out of focus or if there are no markers visible in the shot it becomes a matter of experimenting in post to create a move on the background that seems to work with the foreground. This can be very time consuming and frustrating especially if your actor is jumping or moving.

If you're doing 3D motion tracking you always want to have at least 3 trackers visible. As always the matchmover will be recording the lens and tilt information from the camera, possibly with the help of the coordinator and certainly with the help of the camera assistant. If you're shooting on a set the matchmover should be getting measurements of anything with straight lines that are clearly defined such as the tabletop or windows. With this information they can build a rough CG version of the set. Set drawings are seldom used to build the CG matchmove version from since there may have been adjustments and changes made to the real set that aren't reflected in the blueprints. You want to make sure to build the CG world to what's actually captured on film, not on what was planned. To help with this work the matchmover usually shoot stills and especially Polaroid's where they can mark the actual dimensions on the image. These and the notes will be used months from now when the visual effects are being started. In some cases stereo images are taken or multiple cameras are used to help document the relationship of the objects in the set.

For organic sets such as caves or outdoors in natural landscape small ball markers are typically used. It's important for these markers show up so they are usually ping-pong balls or tennis balls painted a fluorescent color. Bright LEDs can also be placed in ping-pong balls. This is especially useful in darker sets or night shoots. At times a box frame of known size is filmed in the scene as well to provide a defined object and perspective check.

If the scene is supposed to be a close-up of a creature but there is no fixed object in frame then vertical rods may be used that hold a marker in place. As always there should be at least 3 markers.

If it's a large exterior scene on uneven ground a grid of markers may be set down or at least measured. Now the animator will be able to match the creature feet directly to the real ground. On DragonHeart and most of the shows afterward when filming in a large natural setting we used a surveyors transit system connected to a powerbook or a handheld computer that records the true position in 3D space of xy and z.

The matchmover back at the studio creates a 3D ball in the computer matching those coordinates. In the past the computer camera would be moved manually to match the position. Now there are special 3D tracking programs that can do this automatically.

Face Markers
Sometimes we're required to create CG prosthetics. This is done for shots that can't be done as normal makeup work since it's going to change during the shot or it requires removal of sections of the real actor. This is the case with the jaw extensions in Van Helsing and the facial electronics in something like the latest Terminator movie. Small colored dots from an office supply store can be applied to a face or arm. It's also possible for the makeup person to apply makeup marks. In these cases it's important to know where to place the dots to get the best match. Because of muscle changes you typically want some on the cheekbones or area that won't change as much in addition to the edge of the imaginary prosthetic. The animator, model maker and/or matchmover will then have to change to shape and position of the CG prosthetic to match frame by frame.

Note that matchmoving doesn't solve the problem of repeating live action camera moves such as required for twin shots and doesn't provide us with a clean plate. It is possible to take the match move data and convert it into a move for a motion control systems later when you're shooting live action or miniature elements. If you need a clean plate (for paint restoring) then the operator tries to repeat his same movement as accurately as he can without the actors and then the compositor will have to massage it in post to try to make it work.

Low Budget
Most beginning filmmakers want to make as complex scene as possible but it's important to keep it simple and to learn the basics of the craft before overwhelming yourself.

As mentioned before the simplest process is the locked off camera. Attach you camera to a solid tripod and film your different elements, including your clean plate as needed, without touching the camera or tripod. This allows you to focus on the art of compositing without getting tied up in the difficulties of match moving.

If you're creating CG elements measure the set or area and try to create a replica of this. Use real units of measure in your computer graphics program. Measure your camera as well. This would include the height from the ground and the distance from camera. Technically you want the nodal point of the lens but middle of lens or film plane is usually accurate enough to start with.

You also want to record the tilt of the camera. You can use an inclinometer to measure this tilt. You can find these on the internet or at larger hardware stores. You don't need the fancy, all digital versions. A simple type based on a bubble level is fine. These are 3 or 6 inch vertical disks with a flat bottom. A needle always points up to provide a readout the number of degrees of tilt, Place it on something level to the film plane, such as the tripod head plate.

If you can find one of these or they're too expensive then get a simple 6 inch protractor. Tie a knot in the end of a one-foot piece of string. Thread this through the hole in the protractor from the back. Tie a weight such as a large nut or bolt to the other end. Place the protractor upside down with the straight edge of the protractor resting against the straight edge of the tripod head. Read the degrees where the string passes the protractor. You may find in your CG program that you have to add or subtract 90 degrees from this number or you may have to negate the number. There's no absolute position for pan so we don't bother to measure it.

Place your CG camera at this point and use the set you built be your guide to where to place the CG creature or object. You also want to be able to cast shadows from your creature onto this ground plane and any large objects such as tables.

Once you've done these types of shots then you can experiment with 2D motion tracking and 3D matchmoving. Start the 3D matchmoving by using just pan and tilt when shooting.

Wednesday, November 23, 2005

Comments and iTunes

Just so everyone knows, right now when you post a comment it sends me an email and then I have to approve it. So if your comment doesn't show up immediately don't worry, I'm probably just slow getting to it.

On a side note if you have problems using the original feed on iTunes you can click on the Effects Corner on iTunes link on the right.

Thanks.

Monday, November 21, 2005

Filming

Filming live action for visual effects on feature films. I discuss the process of shooting on locations and sets, using references, creating interactions and things to watch for. In addition I give some suggestions of to apply this to low budget filmmaking.
I'll probably discuss moving cameras and matchmoving in the next podcast. Filming of bluescreen, minatures and other elements will be covered in future podcasts.

Transcript
In today's podcast I'll be covering the filming process relative to visual effects. First I'll focus on how it's done on a feature film and at the end I'll provide additional suggestions for filmmakers. I've actually split up this podcast so moving cameras will be discussed in the next podcast.

There are infinite possibilities when shooting a film, which is one of the reasons why visual effects are interesting. I'll be covering the basics of shooting with actors or what we term as live action. Later podcasts will discuss shooting bluescreen and miniatures.

First a review of a few terms I'll be using.
CG stands for computer graphics.
An element is an image that will be part of a composite.
A plate is a live action element.
A clean plate is a version of the shot without actors that can be used to remove any unwanted items from the real shot.

The shooting of a feature film can take two to six months. Much of the shooting depends on the project. Some projects such as Dragonheart are shot almost all outdoors, regardless of weather. This makes it like a camping trip with 2 or 300 hundred other people. Other projects may be primarily on sound stages in front of bluescreens. Most projects are a balance of exterior and stage shooting.

Prepping for the shoot
Before shooting begins it's important that the cameras are checked and prepped. This is handled by the camera assistant but for visual effects we request a steady test. When film goes through a movie camera the camera movement may cause the film to shift a bit from frame to frame. This isn't visible in a typical shot projected on the movie screen but if you composite multiple images you may well see them moving against each other. In some older movies when you watch the titles you may see them shaking against the background. This was because the original camera wasn't completely steady.
To test the steadiness a grid of white lines is applied to a black backing. This can be tape lines on a 4 by 8 foot black. This is filmed with the camera fixed on a tripod or pedestal. Depending on the test the film can be rewound and re-exposed to the same grid offset halfway by a grid space. When this is processed and projected you can see if the camera is steady and repeatable to itself. The preferred steady test is to scan the grid from the camera with your film input scanner and confirm that it's not moving relative to your control system, the input scanner.

Film live action for visual effects

The visual effects crew directly involved with the shooting is fairly small. Normally the team consists of the visual effects supervisor or a plate supervisor, 1 to 4 matchmovers, a coordinator and possibly the effects producer as well. If the show is heavy with animated creatures the animation supervisor may also be part of the team. The remainder of the visual effects crew is back at a facility working on creating CG and real models along with preparing for the full render and composite processes. The full effects crew won't start until a sequence has been shot and edited since they need to work with the footage. Because of the deadlines most shows are editing simultaneously with the shooting so finished edited sequence will be done even before the entire movie is finished being shot.

The visual effects supervisor or plate supervisor is in charge of making sure the required footage is shot correctly to do the effects later. The plate supervisor is called that since live action pieces or elements are frequently referred to as plates. A background plate for a bluescreen would be called BG plate. The matchmover position was created primarily in the digital age. It's important to be able reproduce the camera and objects exactly and that means recording all the camera information such as lens, tilt and also to measure specific items in the scene. The coordinator helps to organize all of this and to facilitate passing of information. The effects producer is normally busy at the effects house overseeing that process but the production itself may have their own effects producer on the location to help the different departments and to make sure things are moving smoothly.

Before the photography begins there's usually some pre-production at the location. Part of this is a key meeting with all the department heads, including visual effects, so everyone is clear on the requirements of each sequences and who's doing what. It's also a chance to flag any problems. Typically the storyboards and animatics are shown to the department heads and the actors so they're aware of what the final shots will look like.

Each day there is a call sheet passed out to all crew members that lists the shots/sequences for the next day as well as when each crew member is required on set. A shooting day is usually 7am to 7pm and night shooting is 6 or 7 pm to 7 am. Shooting is 5 or 6 days a week.

The setup
First thing in the morning is brief huddle of key personnel with the first asst director and director. The director has his shot list, which is the list of all shots he plans to shoot that day. For shots that require visual effects the first task is to figure out the camera position and blocking. A director may run through with the actors first to get a handle on how he wants the scene covered. For camera placement it's important to consider anything that will be added later in postproduction. I typically have a set of storyboards that have been reduced to half size so it fits in my side bag or jacket pocket. I've gone through and made notes about every element or piece of film we have to shoot for each shot and have a technique in mind for each shot. We do a quick review of the storyboard. Since the storyboard is only a guide the director or circumstances may require a change. As a visual effects supervisor I have to be able to quickly determine any implications these changes might mean. Will other elements be required? Does this change the technique? Have we already shot something else that this needs to work with? Will there be any major cost differences?

For Dragonheart I wrote some software for a powerbook that would display the dragon in the correct size on a location still, but we found it faster to take the poseable dragon model in front of the camera. With the actor standing in the scene and the physical model of the dragon we can easily check the composition and framing. I'd have a matchmover measure the distance to the actor and would calculate the scale distance for the model. If the actor was 50 feet away it might mean the model should be 23 and ½ inches away. Now the director, DP and myself would review the framing. Once the initial framing is setup we review the specific storyboard and animatic with the camera operator and actors along with key people. The practical effects and stunt crews start any rigging necessary while the director of photography lights the scene.

To help the actors and the camera operator interact with a creature we try to provide a stand in. For Dragonheart we had a monster stick that was an expandable pole with 2 disks on each side representing the eyes. For something like Mr. Hyde on Van Helsing a 2d foam core cutout was attached to a helmet worn by an actor for reference. Roger Rabbit used 2d cutouts and full-size 3d practical model. If the creature is moving someone moves the stand-in around. The actors can use the eyes as a guide where to look and react and the camera operator can make sure they provide enough room in the film frame for the creature. At least one reference is shot with this stand-in moving around. This can be used as a temp in the edit stage since the action and framing is clearer with the reference. We try to do the majority of takes without the reference to avoid having to do paint out removal of it in post. In some cases though the complexity of the action may require the stand-in be in all the takes.

Interaction
Any time you're combining multiple images you want them to blend together to make them appear to be a real scene or location. To help with this illusion we try to provide interaction of the different elements such as a creature that lifts up the actor and then swings it's tale to knock over a bookcase. This is where the special effects crew gets involved. As mentioned before technically special effects in movie credits are practical or mechanical type of effects. Normally this will have already been discussed with the special effects supervisor who will have planned and constructed some type of rig to do this. If it involves moving the actor or a stunt person then the stunt coordinator is involved. New ideas from the director at the time of the shoot require everyone to scramble to make it happen. If it was preplanned and there is an animatic we use that as a starting point for the timing of the action. If there is no animatic the animation supervisor or the visual effects supervisor is involved in working out the timing with the director. We need enough time for the actor and the imaginary creature or object to react. The asst director will usually provide a verbal cue so the special effects crew can do their part at the right time. If the creature is supposed to speak then someone on the set will be a stand-in for the creature by speaking off camera or this may come from a pre-taped voice. An actual person on the set delivering the dialog is preferred since the timing and dialog can change easily.
Another form of interaction is the lighting from the director of photography. If colored objects are supposed to emerge from a glass then the DP has to create an interactive light on the faces of the actors so when the objects are added later by the visual effects crew they look like they're creating the light effect on the faces.

Rolling film
Each shot and take is noted on the camera report and slated. For visual effects shots there are usually specific shot names or ID codes that relate to the sequence. These names may have been defined months before in pre-production and relates to specific storyboards.
The first take is usually done with any interactive reference material as monster sticks or a stand-in. After that the shots may be done without these depending on the specific requirements.
During each take the visual effects supervisor is making sure everything is working as required. Is the actor's eye line correct? Is he looking for where the creature will be in that specific moment? Has he missed a mark and put his arm through where the creature is supposed to be? Are there additional items that may need to be removed? Will the special effects rigging work and will everything look correct once the shot is finished in post? Are any cables causing a bunching up on the costumes that give away the fact the actor is on wires? Is the camera move correct and timed right? There are a hundred items to keep an eye on.

The actor's eye line becomes even more difficult when there are multiple actors. If you have a lot of extras it becomes very difficult. If you have a small object flying and hovering the illusion won't work if everyone is looking in a different direction. So to handle this you do the run through with the reference and may need to shout out timings so to choreograph this eye motion. You may need to work with the special effects people to create a small target that can be moved around that people watch. For Dragonheart we used an ultralight plane for some shots where the dragon is flying. This provides everyone with a clear idea where to look and the plane itself is removed in post.

Multiple video cameras may be mounted on tripods to provide additional reference for the animators and match movers.
I try to list on my storyboard book any additional items that may be critical to keep an eye on in a specific shot. I've also listed the additional elements that may be required.
Most of this checking involves looking at a video monitor coming from the video camera mounted in the film camera. This is known as a tap camera and unfortunately the quality of the tap cameras is about the same as surveillance cameras. The video monitor itself is at what's known as the video village. There's an operator who runs this and records video of the different takes for reference. It's around this small monitor or two that the director, script supervisor and other key people may be grouped around during a take.

If there are changes to be made the effects supervisor discusses this with the director. Normally you let the director be the one giving directions to the actors to avoid confusion.
Once the director is satisfied with the takes for the main action any additional elements are filmed. This may be the clean plate as previously discussed. This could be some practical effects such as dirt hit or an additional actor. For things like dust hits a black flat may be placed behind the dust and this element would be screened or lumikey in the final composite. If it an additional actor this may be shot against a small portable bluescreen on the location. One of the advantages of shooting these elements on the location or set is the lighting will match and camera position will match exactly. Trying to re-create sunlight months later on a stage and have it match is very difficult. The downside is this will take up more time when shooting the live action.

Once any additional elements are shot references are shot. For 3D work normally a ½ of a gray sphere is shot. This will provide a controlled reference for the technical director who lights the CG scene later. It shows where the light is coming from and the basic balance of the lights. A ½ of a chrome sphere, which may be the other side of the gray sphere, is filmed. This will provide an image for the reflection map that is wrapped around the image. This provides some of the ambient illumination as well as image for the reflection. Sometimes stills are taken with a fish eye lens to provide this same map.
A color card or grayscale may be filmed to provide a color reference. I usually try to have a reference of the object that will be added later. If we're adding a CG version of a clock such as in The Mask I'll move that through the action so the technical director, also known as TDs, can use as a guide for how the material and lighting interact. If there's a creature the model shop may provide a reference material such as section of fur if this is a creature with fur. By trying to have as many real world references as possible the final results will be based on what it would really look like in that environment. Even with fantastical creatures the aim is to make them photo real. It's actually more important to make them photo real since the eye and mind knows it's not real it tries to find any discrepancies.

So finally we have one shot done. There may be another 20 more to do that day, each with their own concerns and rigging. On a large show they may be running 2 cameras all the time to provide more angles and coverage. For complex action scenes they may be running 4 or more cameras at the same time. Any of these shots that will require visual effects will need to be watched and measured. A large film usually has second unit crew shooting additional scenes or pickups and inserts at a different location. Each of these shots has to be dealt with the same way if there are any visual effects.

On a large effects film there comes a time when the crew along with the director and assistant director start assuming that you can fix everything and they may become a bit sloppy about removing things from the scene or making final adjustments or providing you what you need. There is always pressure to keep moving on a film shoot and in some cases it will be cheaper for you to do something in post rather than taking an hour at a cost of tens of thousands of dollars to do it on location. The visual effects supervisor has to weigh these two issues and choose his battles wisely. If the quality will suffer because of production shortcuts then it's critical to flag the director and discuss the issue.

Low Budget
So how can we apply all of this to a low budget filmmaker? As always planning and preproduction are vital for keeping production moving smoothly and keeping the costs down. Make sure the effects are there to tell the story.

Try to do a rough storyboard of all your effects shots. Don't get wrapped up in created elaborate animatics or 3D storyboards. Usually the added value of these, especially for simple projects, is minimal but the time required can be enormous. It's better to put your additional time and energy into the real shot.

Analyze the different elements required to make the final shots. Remember to keep it simple. If you can do it using 2 elements instead of 5 do it with 2. List those elements with the storyboards.

Keep the storyboards with you while shooting and check off the elements as you shoot them.

Do tests ahead of time to check your technique and to determine if there are other requirements when shooting.

If this is a really low budget film you may be directing and running the camera in addition to doing the effects. This makes it even more critical to have a checklist and make sure everything is shot correctly.

Communicate with your crew so they understand what you need done. Make sure the actors understand what's required of them. The storyboards will help here.

Don't rush the shoot. If you don't get what you need or get poor quality elements then you're likely to spend a lot of time in postproduction just to create something marginal.

Be prepared. Have your tools with you. Storyboards, notepad, pens, tape measure, etc. A fanny pack or other bag is useful to hold these items.

Slate and label everything. Try being organized. When you're doing effects work you may end up with several elements for each shot. It's very easy to get overwhelmed but al l the different variations. On a feature film we have people who's focus is to keep track of all these bits.

Double-check your camera settings. If you review the footage on your video camera be sure to cue it up to after the last take. This is to avoid recording over a shot and to make sure the timecode is correct if your camera supports timecode.

Just because you can do something in post doesn't mean you should. As an example if someone left a c-stand in the shot you could paint that out later but why bother when you can just take 5 minutes and move it out before shooting. Don't try to fix everything in post. Balance the time on the location with the amount of work required and the final quality.

Keep the shots simple, especially if this is one of your first projects. Even when on set make sure you're not making things too complicated. When we were filming the The Mask we had planned a wide shot where large props are being pulled out of Jim Carrey's pants. Since this included items such as a tuba and bazooka and we saw his entire body we were going to make CG pants and stretch them to show the objects being pulled out. On the night of the shoot the director changed it to a cowboy framing, which means the bottom of the frame, is between the knees and waist. Jim's costume was a very baggy zoot suite so the stretching pants gag became un-necessary with this framing and costume. I suggested we cut the pants to make them into shorts and cut holes in the pockets. We then had two people shoving real props up into the pant pockets.
We eliminated an effects shot and had something that was better for that shot.

If you're shooting on film, especially 16mm, do steady tests before shooting or your images may jump against each other. If you're shooting film but will be finishing on video make sure the telecine is done with a solid movement. In the past you had to request a special pin registered transfer but film movements have gotten better. Just check with the video house and make sure to steady test it.

If you're shooting video try to shoot progressive if you can with a camera like the Panasonic DVX100. You can shoot visual effects with a standard video camera but the interlacing makes the process a little more difficult. Likewise if you're planning to shoot video and doing a lot of greenscreen work consider shooting on a higher end system than miniDV. You can do greenscreen with miniDV but a higher end system will provide better quality easier.

Shoot your shots as locked down cameras if possible. This will simplify most effects a lot.

Try to shoot a clean plate when possible. To make sure there's a good match you can just keep the cameras rolling and have the actors leave the scene. This avoids the chance of the camera changing or the lighting changing as the sun moves.

If you're going to purchase a composting software try to get one with motion tracking. If you're in school check on educational pricing for all software. And certainly take advantage of cameras that may be available through your school.

High quality visual effects takes a lot of time and work. Even with all the tools available nothing is as simple and easy as you would think it would be. Accept that and keep moving forward.