Showing posts with label special effects. Show all posts
Showing posts with label special effects. Show all posts

Tuesday, July 10, 2012

The Value of Visual Effects



The Value of Visual Effects

There’s often discussions about the costs of visual effects. But for now let’s take a look at something seldom discussed and that’s the value of visual effects.

What are the benefits of visual effects? - Story telling freedom.
Freedom for filmmakers, writers and directors to tell any story they like.  Humans have been telling stories since communication made it possible. Verbal and written story telling can and does cover everything imaginable. A writer has full freedom to do anything including having their main character turn into a giant cockroach. Myths from around the world describe actions and creatures that don't exist in real life. Even the Bible has a number of stories that would be difficult to realize beyond the written word and paintings.

The various mediums of story telling all have their place and good stories are tailor made for each medium. Converting a novel to a film script takes specific writing skills to boil the essence down to 2 hours. It also means that writer descriptions that would form images in the readers mind now need to be generated in photographic reality for the movie viewer.

Visual effects
Visual effects have been used in films almost from the beginning of movies. Méliès used visual effects extensively in the early 1900's. (More info on Méliès) Since that time visual effects have been used frequently and not just for special purposes. Some movies used matte paintings to add ceilings that were non-existent on the sets. Visual effects continued to evolve and provide sights not viable to actually film. Their style tended to be in keeping with the film styles of the day (shooting outdoor scenes on sets, rear projection, etc). But visual effects were not without their limits. Camera moves and other restrictions were simply due to the limits of the technology at that time.

With the advent of digital and computer graphics as tools for visual effects, artists are now able to have full control over their images in a way not possible before. These are in addition to their toolbox of previous techniques including models and miniatures when desired.

Almost all films coming out of Hollywood use visual effects to some extent and even many independent films have visual effects. Keep in mind that visual effects is not just for science fiction and fantasy films. They can be used extensively in period films and even in present day comedies. FIVE YEAR ENGAGEMENT used visual effects. WAR HORSE used visual effects extensively including some of the field shots, leaping horse, etc. FOREST GUMP showed an actor missing a leg.

Visual effects cover such things as:

Creating entirely virtual shots
Changing the background
Creating the background
Adding actors, characters or creatures
Changing actors
Adding objects or props
Removing objects
Obscuring objects
Specialized speed changes
Fixing problems on the set, adding eye effects, removing wig netting, etc.

The visual effects team works closely not only with the director but also the cinematographer. Working with the production designer we can expand the sets that are built or build sets that would be impossible to build for real. Working with the stunt team we can remove their rigs (car ramps, wires), help to provide the visuals needed while trying to maintain reasonable safety and can extend or create a stunt if it’s not possible. Working with the special effects* team we can hide their rigs if required and expand and enhance what they’re able to provide. Working with the wardrobe department we can expand the capabilities of their costumes when required (IRON MAN, BLACK SWAN, etc) Each of these departments are very helpful in providing visual effects with what we require to get the best material.

Visual effects is normally focused on the augmentation or modification of live action but visual effects artists and tools are also used for:

Computer graphics animated films (Pixar, Dreamworks, Sony Animation, etc)
Video games
Previsualization
2D to 3D conversion
Titles
Logos
Special venues and multimedia (in addition of course to films, television and commercials)

Now to those of you who may hate visual effects or computer graphics keep in mind you’ve already seen an incredible number of visual effects shots and never even noticed. Much of the work done is not over the top theatrics. In many cases it’s to allow productions the option of shooting something elsewhere or to fix problems on the set (boom mics, makeup, etc). Even television shows like Ugly Betty did a couple of years with green screen to place the characters in New York. Unlikely that most viewers even noticed.

Next time you watch a period film consider that many of the buildings you see may not exist or may be currently covered in tv satellite dishes. The bay you see in the background filled with ships was likely added.

Visual effects artists and craftspeople have been developing and refining their tools for decades. Digital Intermediates (DI) is used for color correcting films. These and many of the digital tools that film productions use daily were pioneered by visual effect artists.

So we are now at a point where just about anything that can be imagined can be created on the screen and look good. Realistic when required or fantastical when required depending on the production.

When visual effects don’t look good these days it’s likely:

Too little time (changes or additions to visual effects from the director or studio can happen up to the final week of work). This means there’s no final polish or in many cases not even a chance to do a good take. And these days many productions start with too little time to begin with.
Selecting a visual effects company or people that may not be up to the task or lack experience with specific aspects.
Poor shot design
Poor creature design
Not being able to shoot the required elements as planned
Not enough time on set to gather necessary images and data

Freedom
In the end studios no longer have to leave scripts on the shelf for years because they’re not doable (DRAGONHEART, WATCHMEN, BENJAMIN BUTTON, LORD OF THE RINGS, etc). Directors and writers have complete freedom to bring their imagination to the screen and to tell just about any story in the manor they wish to. At least as far as visual effects is concerned.

The amount of control and freedom for a director is almost unlimited. That along with the fact many movies are concerned with pushing the envelope creates some sequences where the believability is pushed too far. Where the onslaught of in your face imagery causes audience overload or eye rolling. This happens with stunts and special effects when they are pushed too far as well and the audience says ’oh come on’.


Box-office

In addition to allowing filmmakers freedom of story and flexibility to change or modify scenes, visual effects certainly help the studio’s bottom line. Film is a visual medium that can be shown and appreciated all over the world. Visual effects can provide unique worlds, views and characters that ignite the imagination of those that see them. They can provide the spectacle that goes with specific types of stories.


If you look at the top box-office list of 25 or 50 films you’ll notice almost all of them required visual effects and in many cases they are full of visual effects.

Here's US top films
Here's the Worlds top films

Hard to find non-visual effects films, especially in the world list.

Studios choose to visual effects heavy films as tent pole films because they’re profitable. With some of the top films earning over a billion dollars the sum total of successful films in which visual effects played a significant role is staggering.

[Note that I’m not saying all films need visual effects or that the film world revolves around visual effects. I’m a fan of well told stories of all types. I’m simply documenting the current state of visual effects and what the potential is. Visual effects do not make a story better or worse, just that they allow bringing certain types of stories to the movies.]

A world without visual effects
Try to imagine many of the top films without visual effects. STAR WARS without space, spaceships, lasers. TRANSFORMERS without the Transformers. The MATRIX without bullet time and impossible physics. AVATAR without it’s world, without it’s plants, creatures and Na ‘vi. TITANIC without the water and the entire ship. ALICE IN WONDERLAND without the world and characters. HARRY POTTER without the magic. JURASSIC PARK without the dinosaurs.

Look at this year so far - AVENGERS, SPIDERMAN, MEN IN BLACK 3, SNOW WHITE AND THE HUNTSMAN, BRAVE, PROMETHEUS and a number of other films with 5 months still to go.

It’s hard to begin to imagine these films without visual effects. Needless to say these films would have not done nearly as well without visual effects. It’s likely they wouldn’t have been attempted without visual effects. Showing an actor saying ‘You should see what I’m seeing right now, it’s fantastic’, seeing actors jumping around in front of a green screen or painted cyc or adding a Prologue at the start of a film to ignore certain aspects (such as tv dishes in a period film) would not tend to make for a great movie going experience. A play, musical or opera tend to be confined to a live stage and as such the audience accepts the limits as they’re presented. These days however most film audiences are looking for a sense of reality in the movies (even if the movie is a fantasy).

As we can see visual effects provide both monetary and creative advantages to the studios and filmmakers. They play a very important role, especially today, in not only the movie industry but in television, commercials and other content.

Visual effects and the shooting process
Many directors in Hollywood not only accept visual effects but embrace them for being able to provide the vision they need for their film projects. These directors usually get the most out of their visual effects budget. However not everyone agrees. Some directors would prefer to consider effects a necessary evil and put them lower on the priority list, even when working on a super hero or talking goat movie. In this case the super hero powers or the talking goat are likely the key things in the trailer and one of the main reasons the audience is interested to see the movie. But some choose not to acknowledge the value that visual effects can bring to their project.

In some cases the directors don’t interview potential visual effects supervisors but simply let the studios or someone else make that selection for them. Do they approach hiring of the cinematographer and other key creatives in the same way? Unlikely.

The attitude of the director, producer and 1st assistant director has much to do with how successful the shooting process is to the visual effects crew. One of the aspects of creating great visual effects is to shoot the footage correctly for visual effects to begin with. This means typically having the visual effects supervisor and a small group of people to take references. Because we have to create and very precisely combine multiple images together we want to make sure we know exactly where we can place the objects and make sure to light them to match. Shooting references involves holding up a gray and silver sphere in front of camera or shooting with a special camera setup.

When shooting, a large amount of time is spent setting up to get the shots. A 2 hour movie may have a shooting schedule from 40 to 100+ days. Each day can cost $100,000-$300,000 or more depending on the size of the project. Each setup takes time. The grips may lay down dolly tracks or a ‘dance floor’ to shot. The cinematographer spends time lighting the set and the other departments prepare. The audio department records 30 seconds of silence at each location to make sure they have the raw materials they need in doing the final sound mix and edit later. The entire crew is silent during these takes. When an airplane flies overhead it’s likely the crew holds until it passes so they can record good audio. Yet when the visual effects team needs to spend a minute shooting a reference it’s not unusual to get eye rolling and gnashing of teeth. “You’re slowing us down. We’re trying to make a movie here.” are common phrases heard at that time. They easily forget that most of the movie is being completed later in visual effects and visual effects are critical to the success of the movie. As pointed out visual effects may have enabled the project even to be made but some crews look at visual effects as the lower department. On the better projects it’s all part of the process from the beginning and not a problem.

There may be times during shooting that the visual effects crew is not scheduled or have been released for the day. But that doesn’t stop production from sometimes attempting to shoot visual effects on their own. They don’t try to shoot shots if the camera crew isn’t there. They don’t try to do a stunt or start a fire without their respective departments being there.

On shows with a lot of visual effects there’s the notion that anything can be done and that it’s all in the budget. Rather than removing something from set or location (8 x 8 ft silk, compressor, truck, etc) the crew will sometimes ask if visual effects can simply remove it. They suggest they can cover it green as if that provides us the magic fix. If production is running behind schedule, something isn’t working (such as a prop), or hasn’t arrived (contact lenses, etc) then production has a tendency to push that onto the ever growing visual effects list. We barely have enough time and money to do the planned work let alone this ‘extra’ work but since the studios typically have visual effects and live action as different budgets that is not of concern except to those who see the big picture.

And of course the cost of visual effects is brought up frequently.
So why use visual effects (in addition to the reasons provide at the start):
1. It’s cheaper than the alternative. Consider how much it would cost to destroy a city or a planet. Visual effects don’t look as expensive in that context.

2. It offers more precise control. Since time is money on set and the director may want exact control or the option to precisely change it later, visual effects may be the correct option.

3. Not enough time. Maybe you have the money to build an entire castle but do you have enough time to do so before shooting starts?

4. It’s not possible any other way. Floating space ships, talking dragons, people flying and shooting lasers are not exactly easy things to obtain. How long would it take and how much money would it require to build the Transformers? How long would it take to genetically produce a dragon?

Keep in mind visual effects models and environments have to be created from scratch. We can't rent a house to shoot in or props to fill it. We can't rent a field to shoot on. We have to build and paint everything from scratch. When we move our characters or creatures we have to make sure their feet touch the ground without going into the ground or floating above it. Many of the things taken for granted in live action has to be worked out in great detail in visual effects.

Summary
Visual effects allows filmmakers an incredible freedom to bring any story they wish to the screen from a creative and technical standpoint.

Visual effects  are used in just about all films, above and beyond just science fiction and fantasy films.

Visual effects film do very well all over the world. The top box-office films of all time use visual effects and most use visual effects extensively.

Visual effects artists are the only group involved in Hollywood filmmaking that don’t have a union. Most are freelance project to project just like other film jobs. Visual effects craftsmen work long hours like other film people and at times are likely to be putting in 80 or 90+ hours a week for weeks or months at a time due to compressed schedules and last minute changes. Much of visual effects is outsourced around the world due to film tax incentives just like some of the jobs in Hollywood. Some artists have to uproot their families and move to other countries in an attempt to remain employed. I believe to get the best out of people you should respect them.  Given all that visual effects brings to films, the people who make them and the people who watch them, I think visual effects artists deserve the same respect as the other departments and workers in the film industry.

Related Post

The Miracle of Visual Effects, will it continue?  - images show what visual effects can do

Why do Visual Effects cost so much?
Visual Effects are Inexpensive


*Special effects are explosions, breakaways, wire rigs and other on set work as opposed to visual effects which is about images and primarily done in post-production.


Saturday, March 26, 2011

VFX Interactions

Interactions
Most visual effects are designed to integrate with live action images. Whether you're creating a cg creature, cg background, physical model addition or even 2 live action elements, the intent is to match these elements together so they look as if they were photographed together. That means matching lighting, camera angles, color and other aspects.

But visual effects are more than still images. To help the illusion of integration even more you should look to create interactions whenever it's appropriate and possible.

Interaction and the special effects crew
Special Effects are the things done in front of camera such as fire, break away glass, etc. They're sometimes refered to as practical effects or mechanical effects. Interaction should be planned in pre-production as the shots are being designed (storyboards, previs).  The vfx supervisor will work with the special effects supervisor to determine how interaction can be done during filming. In some cases it may be as simple as a fishing line (monofilament) used to move a hat that a cg creature is supposed to pickup.  Or a gust of wind from a fan on set. In other cases special effects or props may have to build something elaborate which will require time.  This is why it's best to discuss in pre-production rather than waiting until you're on the set.  There will be times when you will have to throw something together on the set but preplanning provides the most options and most likelihood of success.

Any rig or setup should be tested ahead of time with enough time to make corrections if necessary. If it doesn’t work on the day of shooting for whatever reason you'll be stuck with it or will have to abandon it.

Keep in mind what you're trying to simulate and how that should look. Reviewing related references ahead of time is always good. On TIME MACHINE we had a morlock who was supposed to crash into a stand of bamboo trees.  The special effects team had rigged some of the trees to simulate it the way they thought it should work. The bamboo trees had been pre-scored (partially cut) and then fell over, cut in mid section. Not exactly what a large creature crashing into them would do to the trees. There was another test with cables to each tree but we worked with them and they build a simple metal plow that would be pulled by a winch that literally crashed into and through the bamboo.  Now we had something that would match what the animation would require. We would have to paint out the rig where the creature didn't cover it but that was much better for the overall look of the shot.

Always keep an eye on the interaction and imagine the final results. If the on set action is wrong (it's at the wrong height, it's moving too quickly, the rig is shaking, etc) then you need to correct it then and there.  Trying to force an animated character into contortions simply to match what was shot will not make a good shot. If there are major problems you may have to skip the interaction or may have to do it all as post effects.

For DRAGONHEART we had a number special effects rigs for interaction. Special effects rigged up multiple air canons to spray the water when the dragon bursts through the waterfall. This is when your prep work in pre-production comes in handy because you can provide them with the size and placement necessary of the creature or virtual set to be added. For the shot of the dragon tail going into waterfall we had special effects build a full size black version of the tail. This was pulled through and once the cg tail was added later the water traced the contour and provided the interaction to help place the dragon into the world on screen.

For the scene at the end where the dragon is in chains we had special effects build a pipe rig that acted like a teeter-totter. Chains were draped accordingly over one end of the rig, which was sized to match the dragon’s horns. A special effects crewmember used the other end to move it slightly while Dennis Quaid removed the chains. Other chains on the dragon were cg.  By doing this we not only got the correct motion and look of the foreground chain, we also gave the actor an opportunity to act with his missing cg actor.

For the end of the film we see a spirit flowing by a group of people. In this case wanted to get interactive light on the face of the villagers. The camera and lighting crews worked with the special effects crew to build a translucent box with colored changing lights suspended on wires and moved by the crew.  We removed the light box in post and added a particle spirit to complete the scene.  Now the glowing cg image seemed to be illuminating the actors and provided the illusion it was really there.

There are many other examples on that film including requesting the special effects crew lay in the tall grass and make snow angels (move their arms and legs while laying down) to move the grass when the dragon lands. Special effects welded 3- 55 gallon drums together and we had this dropped from a helicopter to simulate the dragon diving into the lake.

In all of these types of cases you end up with the correct interaction, the correct lighting, correct camera match since it's all happening in the shot. This also makes it easier for the director and the rest of the crew since they can see the action on set. In post this provides the editor with a better sense of the action.

As soon as multiple things start happening you need to work out the timing. First this happens and then 1 second later this happens and then 2 seconds later this other thing happens. If previs exists it will provide a good reference but there’s almost always adjustments to be made on set. If the action is related to something close to human size  the vfx supervisor may pantomime the action on set so the director, actors, camera operator and special effects crew get a sense for the timing. If there are a number of these types of shots then production may hire an actor to play the role on the set.  Ideally after the run through the shot would be done without the standin actor (to avoid a lot paint removal) but in many cases it's worth having them in the scene. This provides a moving reference for everyone.  The director and the asst director will try to get through these shots as quickly as possible but you should push to shoot 2-3 takes if possible to have different timings.  Invariably there are new ideas later or the creature or type of action is refined.

Note that in many cases it's not recommend to paint the rig or outfit the person in green or blue.  In many cases you won't be able to easily pull a matte anyway and more than likely you'll have colored bounce light that will need to be removed.

Post-production
While filming keep notes of the various bits and pieces of additional elements that will be required for the finished shots. Flames for torches, smoke from the house, water splashes, etc. In some productions you can shoot these elements with the special effects crew at the end of production.  For DRAGONHEART special effects built essentially a waterproof wood frame probably 20 x 20 feet and 1-2 foot deep. This was used to shoot additional splash elements.  At ILM we had special effects and camera crews available so we would plan an element shoot such as the flames to match the top of the coach in VAN HELSING or blowing leaves or dust hits to match the motion of creature foot steps.

Many of these types of elements (smoke, fire, dust, water splashes, rain, etc) can be shot against black.  Only use a colored screen if you're shooting something that is multiple colors. Use video and or stills images from the original footage to get basic framing. Shoot wider to make sure you don't clip the element off. You can blowup a bit in the comp but if the smoke or fire hits the edge you can't reduce it or reposition it.  Lighting for rain and splashes is usually best done as cross back lighting. Backlit smoke also works well. These days you can actually do a quick comp on your laptop depending on your camera system (if it's digitial of course).  Depending on the relative size of the element action compared to it's finished size it may need to be shot at a higher frame rate.  You can slow down in post but if you have the option to shoot at a faster frame rate, do it.

For those who only have experience with computer graphics they will likely try to solve all of these elements with computer graphics. The problem is cg simulations tend to take a long time to look correct. It’s can be very efficient to shoot elements if you're prepared and know what you're doing and the results have all the nuances of reality. You won’t be spending days debating whether it looks real or not.  It is.  The key advantage to cg is you can sometimes tweak it to a fine degree but that takes time.  In some cases the scale of the effects elements may make it impossible to shoot elements for.  You may also shoot elements and then modify, retime and distort as necessary to fit the particular needs of the shot. The vfx company should always try to keep the elements they shoot based on their contracts.  There are some elements that require very specific alignment but many are likely to be useful in an element library where you can simple re-use elements from previous productions.  These end up being used a lot and come in very handy when you need to stick in a small smoke element here or there.  In some cases a vfx company decide to spend a day shooting generic elements to have on hand.

In post-production you may have to help the director and editor determine which take works best for the animation to be added, especially if there's not a clear performance issue of the actors in the scene.  In some cases I’d take the video versions of the takes and do quick mockups to check for timing and position.

ArtBeats and I suspect a few other companies offer elements that could be used in smaller productions.

For more info check out the VES Handbook
which has articles on shooting elements and providing references for the actors eye lines.