Thursday, January 15, 2009

Brian Pohl - Digit Magazine article

1. What are the key stages in your process for creating an animatic?

Well, essentially it all begins with a script or at least an idea. The studio or production company usually provides us with an initial draft script and a shot breakdown, which allows us to analyze and bid how many vfx shots are planned for the film. With the aid of the previsualization supervisor, the VFX supervisor and director can determine which sequences require the most conceptual and technical attention. If the project is an animated stand-a-lone film, the process is similar but additional attention is given to the process of rough and final layout, which is an entirely different process and occurs a little further down the production pipeline from previs.

Previs for animated films is entirely conceptual in nature and works in conjunction with the story development team to refine the boarding process in 3D. The layout department will then translate that conceptual previs into the confines of the animated 3D environment. Live action film, on the other hand, not only has a conceptual element, but may also be saddled with specific technical needs to address real world situations and stage space issues in advance of shooting. Animated films are far more forgiving thanks to working entirely in a digital environment.

Once the client’s expectations have been fully clarified and the job awarded, the previs team is assembled and begins work on two primary tracks. The artists are normally assigned to various asset and model-building tasks, while the previs supervisor normally creates a preliminary scratch and editorial track utilizing storyboards provided by the studio. This 2d “board-o-matic” is helpful in determining shot timing and pacing within the sequence. The previs supervisor also breaks sequences down and assigns shots to various animators within the previs team.

Asset building and “ramp up” time is usually the slowest stage of the entire previs process and can require up to several weeks depending upon the complexity of characters, environmental needs, and motion complexities. Usually a well-established previs company will have a number of these assets and IK rigs already available, however, each circumstance is different and the time required can change.

Once asset building and initial timing is complete, shot construction begins. A typical sequence is normally assigned to a small 2 or 3 man team. Smaller teams allow for greater uniformity and continuity between shots. They will proceed to animate individual shots that are then assembled into a cut sequence by the previs supervisor (or editorial department in a larger studio). It’s the previs supervisor’s responsibility to clarify and manifest the director’s vision for the film to the individual artists. As the sequence comes together, there will be various shot and sequence reviews by each of the major supervising powers. The Previs/Layout Supervisor first, the Animation/VFX supervisor second, and the Director third. This review and revision paradigm continues until the sequence finalizes into its first final form. Additional sound fx and sweetening are done to round out the sequence and it is presented to the Director for final approval.

2. What do you need to consider before starting?

First and foremost, it must be determined if the sequence in question is being constructed for conceptual and storytelling purposes or if it needs to be more technical in nature. Conceptual previs is used primarily to tell the story, determine timing, define camera angles / lenses, and figure out which shots work and don’t work within a sequence.

Technical previs is more about determining exactly how far the camera is from an object, how much green screen space the director has, potential gimble requirements or if there are any physical restrictions in real world space that may interfere with actually obtaining a shot. Its goal is to provide hard data.

It can be very difficult to attempt to do both processes at the same time. Finish the conceptual process first before moving on to the technical issues because the one will ultimately drive the other.

Additionally, a strong understanding of the timeline and budget will restrict various options concerning the look and level of detail applied to each sequence.

3. Any tips for the best way to approach the task?

Communication between all the supervisory powers is essential.

If working on a live action film, obtain the camera package and film aspect ratio details from the director of photography and ensure your digital cameras correspond precisely.

Shot tracking aids the process of supervising the work.

Review shots and sequences on the previs supervisor level daily, while leaving the Director to review larger milestones. Daily interaction with the Director sounds nice, but it can rapidly spiral out of control if micro managing starts to occur. A proper balance between the director and the previs team must be found.

Don’t worry too much about character articulation in your first pass. Step animate and pawn characters to obtain simple blocking and camera positions first.

Try to utilize a referencing system in your 3D program to swap out or update characters easily.

Use hardware rendering to speed up production. Use software rendering for the final version, if time permits, or if the scene is heavily dependant on environmental rendering factors that cannot be adequately visualized in hardware rendering.

4. Are their different techniques for different outcomes?

Previsualization is very fairly universal but can mimic nearly any form of cinematic style. The point of previs however, is to make the movie accessible for review to the director before committing larger amounts of money to an unproven shooting scenario. Shooting time on set is far more expensive than a small 3D team working behind the scenes. It reduces the director’s stress level and provides him with a detailed shot template. If that can be done with miniature objects and a handheld mini camera, 2D cut-outs in After Effects or full 3D animation, the end result is still the same; a more efficient production.

5. How complex do animatics have to be? What is the general level of complexity?

Animatics come in all levels of complexity. They can be as simple as 2d scanned cut outs assembled in After Effects or lush 3D environments and articulated characters that nearly mimic the final product. It’s all dependant on budget, philosophy model (conceptual or technical), timelines, and the director’s need for precision. Experienced directors, especially those from a VFX background, may not need to see the intimate detail because they can “see past” a low rez, non textured object where as other directors require high levels of detail in order to satisfy their need to “see the movie” play out in advance thus proving a concept or evoking the proper emotional response. Hardware rendering and playblasts along with limited modeling, texturing and step animation are generally considered the “norm”.

At POV we prefer to stand out from the norm by providing fully articulated characters, robust animation, textured environments, lighting and software rendering for a refined look. The extra effort really helps sell the emotional quality of storytelling.

6. Any tips on how to edit and polish the animatic?

Editorial is the best time to start correcting issues of continuity, screen direction, and timing. Allow your artists time to see the cut in progress rather than waiting till the very end to see a finished first pass. This will allow for a more rapid response to gross errors in continuity and screen direction. The more artists you have on a sequence the more difficult this becomes to manage so keeping sequence teams small comes in handy. Make sure your previs artists are trained in cinematic language and concepts. They should be fully versed in understanding composition, continuity, camera angles, and other “rules” of filmmaking.

7. How do you integrate the pre-viz work into the production workflow?

This is highly dependent on which philosophy of previs you’re using on the film. Generally conceptual previs is strictly used as a storytelling device and is rarely used to transfer hard data to a vfx company. However, if it is your intent is to integrate your work directly into the production pipeline a strong working knowledge of the vfx company’s chosen software and procedures are in order. Specific issues like knowing the proper unit scale, rotational order, precise camera back settings, aspect ratios, lens packages, set and environmental factors, and data exporters will be necessary. If your software is different from the vfx company’s software, you may need to build specific plugins to export your data to their format, or utilize software that supports .bhv or .fbx file formats. As long as you only animate what a real world camera can do, you should be fine. Cheating previs to elicite faster turn around times only brings misery down the road.

8. Can you think of any do’s and don’ts on the subject of previz and animatics?

1. Always use the proper unit scale for the show and work in real units when possible.
If a director wants to know exactly how high the camera is off the ground, you need to tell him in real world units, not some arbitrary value.
2. Do not scale objects in order to animate forced perspective.
Scaling objects to increase the speed of an object traveling to or away from camera is bad previs. Use a proper lens instead. If you can’t do it in the real
world, with a real camera, don’t fake it in previs.
3. Avoid freezing transformations or animating the pivot point once animation begins.
A number of VFX houses request real world locations of objects and camera
data after completing previs. Freezing transformations or modifying the pivot
point during the process will report an incorrect offset to the objects’ location.
4. Release models for referencing with origins always at 0,0,0 and the pivot in the proper place.
Failure to do so will cause a cascade in the positions of models when updated in
the referencing system.
5. Don’t animate focal length unless specifically asked to do so.
Animating the focal length is ok for specific situations. However, if the film is
shot animorphically, focal zooms may introduce a considerable amount of shake
into the shot, making tracking and precision alignment in the compositing stage more difficult. Dolly the camera instead.
6. Don’t change the established frame rate to speed up or slow down animation.
If you have to speed up or slow down the speed of the animation, do it properly
by modifying the keyframes, not the frame rate.
7. Don’t alter the digital camera’s aspect ratio or aperture once established.
Once your digital camera back is aligned to match the DP’s lens package, changing it will certainly cause problems and lens values may not match.
8. Don’t change the rotation order of the camera or objects once established.
As with translational information, VFX houses generally have a specific rotation order for cameras and objects they wish to maintain. If you are providing data to a VFX house and you have to change the rotation order of an object or camera to prevent gimble lock, be sure to annotate the shot so they can reorder the data accordingly.
9. Use correct naming conventions and version numbers.
Make it clear and self-explanatory.
10. Use only the approved lens package for the show.
The DP has a specific range of lenses available for the director to choose from. Using non-approved lenses or odd sized lenses that don’t exist doesn’t help anyone.

Monday, January 12, 2009

Focus on Peipei Yuan previz with XSI

Interview with Peipei YuanFreelance animator Peipei Yuan talks about creating previz sequences for blockbuster movies, her second career as a stuntwoman and breakdancer and women in the cg industry. Her feature credits include Spider-man 3, Pirates of the Caribbean 2 & 3, Superman Returns and Matrix Revolutions.June, 7th, 2007, by Raffael Dickreuter, Bernard Lebel (origin)
....It's been a blast as a freelancer in the LA area because I've had the opportunity to work with many amazing artists on different movies and jobs. I enjoy working in the art departments, being surrounded by so much creativity imagination and ideas. The most enjoyable part of previz work is working with directors to help them figure out significant sequences in their movies. I also like working with different places because it keeps my on my toes and makes projects exciting.
Tell us about how previz was used on recent projects you worked on and how much of it eventually of ends up on the screenI worked on Spiderman 3 and had the opportunity to work with Sam Raimi and some amazing story board artists like Gabe Harding, Jeff Lynch, and Rick Newsome.
A lot of the shots that I worked on ended up in the movie. It seems most of the shots that require previzing, tend to be some of the most refined and dynamic shots, which help hype up the movie. There were many complicated fights and sequences in Spidy III. Along with Gabe and two other artists, we planned out the Black Spidy and Sandman fight in the subway tunnels.They began to shoot the sequence even before we were completely done with it. Sometimes there were moments I refer to as "DURA-VIS" when they need previz shots done right away so they can figure out how to shoot them on set.In general, I think the story board artists worked hard to incorporate the previz in to the best type of story boards. I also worked on some dream sequence shots with Rick Newsome. I was really surprised that the "Italian Suit" sequence that I prevized was not cut. It was one of those sequences that I felt some people were questioning the necessity of me previzing it. Sam had asked me to choreograph some dance moves for Tobey to do strutting down the street.I think since Sam knew I was a dancer, he had asked me to act out a couple of the actions in his office, and then decided to have me previz it. I created a cute sequence with some of my simple dance moves, and edited it to one of my favorite greasy beats band funk songs, and the whole sequence with all my moves ended up in the movie! It was funny animating dance moves.

Spider-man 3
I was on an all male team of 5, under proof inc. Charlie Gibson as visual effects sup, and rich lee as previz lead. It seemed as though Gore utilized previz not only look and feel, but also story telling. He wanted nice looking previz, with characters that showed facial expressions, and we worked hard to make the previz look nice with effects and nice textures. We used Maya for the previz, and I was lucky to work with talented artist liks Marc Chu from ILM, Scott Meadows, and Robin Roepstorff.specifically,For II: dead mans chest, I worked on the kracken attack sequences where the kracken tentacles are attacking the black pearl, as well as some shots involving the flying dutchman. I found Maya's particle instancer to be very useful for wood explosions etc.For III, i worked a bit on the GreenFlash and some shots in the end when Davy and Jack are on a mast fighting over the chest that contains his heart, I also worked on some shots at the end of the movie.
Tell us how it is working as a previz artist on productions. Does it include a lot of pressure, long hours and tight deadlines or do productions now leave enough time for the process?
It depends on the production. From my experience, commercials and music videos are the worst time pressures. Usually all nighters and weekenders are required. For feature films there are moments where we have to stay late to get deliveries out for presentations, but generally the schedules are not as severe. It's all pretty stressful when some people in the industry don't understand how long previz takes, and demand long difficult complex sequences on the fly.
What projects do you consider some of the highlights of your career so far?
Pirates of the Caribbean, Spidy III, Sky High, Chronicles of Riddick, The Panic Room, Van Helsing, Elf, The Matrix Revolutions. Right now I'm on National Treasure II with two other female previz artists who have been doing previz for a while. We are like sisters and it's really refreshing to be working with all girls for the first time. We're cranking out a car chase sequence... Hot stuff... Girls can animate car chases too...

Do you have any funny story to share that happened during a job of yours?
Too many... it's really funny being one of few women amongst so many male computer geeks. One of my most favorite moments is when I was working late hours at PLF on this music video for Mariah Carey called OH BOY. It was all very stressful, we were all lack of sleep, and it was 4 am in the morning. Kent Seki, the animation supervisor was on the phone with the clients getting comments from them and apparently they were very stressed also, and demanding deliveries sooner. We were all sitting there quiet listening to him speak loudly to the clients, his voice was getting louder and more agitated, and finally when he got off the phone without taking a breath, he started ordering everyone around to do tasks. Then he proceeded to yell "EVERYONE JUST CALM DOWN". I turned around to look at him in the center of the room, and no one was saying anything, everyone was just quietly clicking away at their workstations. It was a great moment we all laugh at all the time, he was being Hector the Projector.
How was it for you being one of the fewer women in this industry?
It's been fun. I notice that because I'm not a man, I don't really have to battle with male egos. All the guys seem to act differently towards me, than they do amongst each other. I feel that most of the time I'm not afraid to say "I don' know how to do it, but I will figure it out" whereas, I feel some male animators don't feel comfortable admitting when they don't know how to do something. Not all male animators are the same, but I've noticed there is sometimes a lot of dissension amongst each other. I feel like being a woman makes it easier to work with other male animators, directors and storyboard artists. There are some actions and animations I feel I'm more knowledgeable about because of my feminity, like animating the way women move, or dance, or fall, or react. In previz I get to study and animate many different things, from creatures like werewolves, Draculas, Animals, to mechanical objects like cars, engines, the inside of VHS machines. It's been fun animating drifts and peel outs in car chases, as well as what really happens in side a VHS machine, or how a Volkswagen turbo charged engine works, or how a soldier blows up.I enjoy being a previz artist because I am required to be knowledgeable about everything, and not getting pigeon holed in to just doing ONE thing. I have to know about everything from 3d modeling and animation, to 2d texture creating, to texture mapping, rendering, editing, and sound editing, timing, look and feel. The best part is being involved with the development of the story and shot compositions.I don't like getting pigeon holed in to one thing, so that's why previz is perfect for me, I like to do a little of everything.
Pirates of the Caribbean 2 & 3Do you feel this meant disadvantages or advantages for you?Advantages because it's always nice to break up the male testosterone in a work place. I like hanging out with the boys... It's nothing different from everything else I've done in my life.
What features of XSI do you find very useful and which areas should be improved?
All day every day I compare Maya to XSI, since I've worked heavily and intensely in both softwares doing previz and final work.There are things here and there that I would love in XSI that are in Maya, and vice versa. Over all, I really love some of the animation tools in XSI, like the ease of expressions, making custom parameters, saving presets, the graph editor. I feel XSI is a great standalone software for previz. As well as the OGL mode for hardware capturing on the fly.But for a detailed description of my favorite and least favorite aspects of XSI:(All of these assessments were on different machines, but mostly high end workstations, and agreed upon by my female previz friends.) It happens to be that I compare to Maya since it's the only other software I use for previz, and it really helps me properly assess what is needed in both softwares. I started using XSI for previz and visual effects in 2000 and most of my Maya previz work was from 2003-2007 in Chronicles of Riddick, Sky High, Pirates II & III, and Spiderman III.
Generally, XSI is great for polygon modeling. i generally use XSI to do quick modeling even to import in to Maya.For previz, the measure tools in Maya are handy, how you can interactively move your nulls and the distance updates. I would really like an XSI measuring tool, that can measure length of a non linear curve as well as two points on a curve.I love how XSI deals with origins, pivot points, centers, freezing transformations, and general working with pivots and nulls, as well as the child compensation mode that Maya lacks. I like the hierarchy setup in XSI better because u have options to have child compensation on or constraint compensation.I like how the interactive pivot in XSI works, and allows you to move the pivot anywhere, just by hitting the alt key. The way freezing centers work in XSI are in certain ways better than Maya, since you can't freeze a null so that it's off in space, but the transforms are all zeroed out.
I love the fcurve editor in XSI, because of the preciseness in the handles, and typing in values for length of handles as well as angles.The dope sheet is Maya seems to work more smoothly. The XSI dope sheet is not user friendly, and seems clumsy and inaccurate in manuevering key frames around like Maya is.I don't like how XSI by default re-evaluates fcurves when you add keys in between keys.there should be an option to the way you would like your fcurves to interpolate after you've added keys. Maya does a better default job of interpolating keys on existing fcurves the timeline in Maya is very useful especially along side with character sets. I hear there are character sets in xsi6 but i haven't used them..i like the XSI mixer, always have, it works well to save clips of animation out and re-map the fcurves on to other characters with the same rig setup, as well as combining keyframes with source clips very conveniently. i like being able to make cycles, and deactivate certain channels for detail animation.For instance if i create a walk cycle, i can bring the clip on to a character and deactivate his head channels so that i can manually animate his head looking around wherever i want it to but still have the walk cycle.Animated constraints are easily accessible in XSI, as surface deformation animations, which come in handy all the time.
I love Maya particle effects especially the particle instancer, the user interface for Maya's particles is much easier than XSI.
XSI passes are the best for final. the passes in Maya aren't as useful.
The user interface for tools, that show real time update on adjustments is very handy in XSI. For instance when i am doing polygon reduction, I can just move the sliders and see the model update in real time, as opposed to Maya, i have to type in the value hit enter, and then see my results.XSI transparency sorting is much better in OGL mode. Which is what we use in previz a lot. The default set up is much better. Maya doesn't handle transparencies in OGL very well. I like the drag and drop function in the software, you can drag images right in to the render tree.
Anything you would like to say to the CG community?
I'm interested in hearing from previz animators/artists or visual effects artists who are also stuntpeople, martial artists, bboys and bgirls. Since these are two things that take a lot of time, it's rare to meet people who are passionate about both. I'm also interested in hearing from people on their thoughts and experiences doing previz, and maybe seeing other people's work. So check my website out at

Saturday, January 3, 2009

differences between previz for animation and live action

Thanks to vfxworld's Bill Desowitz for this article

and Tara DiLullo for this article which reports on the burgeoning previz industry by interviewing six leading indie companies. Both are from 2006.

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