MPC Shanghai VFX Supervisor Andy Steele talks through the process of creating the Coca Cola T-Rex.
The two weeks that we had to prepare for the T-Rex shoot were vital to the overall success of the project.
The first things to consider were the look, scale and behavior of the T-Rex. Mark (Toia, director) briefed us in detail about the overall aesthetic of the dinosaur. With his director’s board we started to develop a full understanding of the action of the sequence. We then started the modeling and look development of the T-Rex, including skin color and facial features.
We needed to consider that our T-Rex had to transform from ferocious during the jungle sequences, into a “happy pet” at the end.
To help achieve this effect, the CG team made some smart decisions on animation controls, allowing the animation team to express the change through subtle face changes and ‘wobbly bits’. The puppet rig ended up being very simple with some extra controls. We considered adding extras such as muscle systems, but because we had only four weeks post shoot to get the commercial on tape and to the TV station, time was too tight. We depended on the creativity of our animation and rigging teams to come up with solutions so the animators could hand-key these extra details.
Once we had a workable rig, we took a DSLR up onto the roof and shot the storyboard frame-by-frame.
To achieve the director’s board, we measured the general dimensions of the T-Rex for each shot and where he would be in-frame. We had decided that the dinosaur was going to be around 5m tall, 11m long and 3.5m in pursuit mode. Rehearsing where such a large character was going to be in-frame was essential preparation. When I arrived on set I had already had a semi-formed picture of what might work for the shoot, which eliminated any potential procrastination.
Meeting the Director
When you meet the director for the first time, it’s important to create the best impression, because trust is essential.
Mark drove me to the shoot location, Brisbane, which is also his hometown, so we had around an hour-and-a-half to get to know each other. In that first meeting we ran through in detail his expectations for the shoot. He wanted to shoot fast, using hand held or mono pod, as everything would need to be shot in natural light across one day. We would need to travel light, as we would be moving on foot between locations in the bush.
The first six hours of shooting were going to be in the bush, away from base camp. I stripped my equipment down to the essentials:
- Walkabout DSLR for texture and references
- Fish-eye DSLR and tripod
- Macbeth chart for color calibration
- Measurement tools
The main purpose of the shoot is to capture the principle photography. It’s important not to over-supervise and become a hindrance to that purpose.
Throughout the shoot, communication was essential. Apart from a key duty, the recording and capturing of the principal camera’s information such as lens, height, pitch, Macbeth chart’s for color calibration and set diagrams.
I was required to leave set and take HDRI’s for the lighting team and reference photos for textures.
We were constantly moving between locations so it was important to choose the right time to do this. It’s crucial information for the CG artist, but you cannot hold up the shoot. Once they had finished in the particular location, I would spend 15 to 20 minutes shooting alone, before running to catch up while they were setting up for the next shot.
The director made a point of communicating his vision for each shot beforehand.
This included the T-Rex movements and his proximity to the actor. On the ridge, the director, supervisor and crew came up with simple solutions to help Mark and the actor understand the dinosaur’s actions. For instance, for the roaring shot, one of the props held a white piece of one-meter poly-board to cut the light on our actor. As our dinosaur comes forward and roars, beneath the camera and out of shot is the other prop hand with a leaf blower, creating a blast of ‘breath’. It was a simple but effective way to synchronize the action and shoot a clean plate.
That first practice run with the DSLR really kicked in at this point.
These were the performance shots with interaction between the actor and a full CG creature. You can’t prepare for every eventuality, but being prepared for some of the challenges presented on the shoot day is essential.
Agency creatives, client and director are all heavily involved in the postproduction process.
Effective communication between all parties is key. Everybody needs to have confidence that the story is being told correctly. It’s our job to make sure everyone is on the same page during the edit.
When we received the first draft of the edit from Mark, we took a single frame from each shot and drew a crude T-Rex to help plan action and framing.
This gets everyone is on the same page from the beginning. The animation team, using some of the on-set information, positioned the T-Rex in one key pose, in shot, with the correct camera. We then sent the FX board to the director for comments and approval. This is a good use of your time prior to edit approval.
Once the edit was approved, working closely with the director, the team put together an animatic.
The key considerations at this stage are framing, story telling and action. After a couple of rounds with the director it was approved for presentation to the agency, and the project could truly begin.
The production was led by the Shanghai team, but it was a truly global effort.
We received fantastic support from the MPC studios around the globe. It required amazing co-ordination from supervision and production teams on each site. In Shanghai we had an animation team, FX, Lighting, compositing, look development, color grading and online. We had our lighting lead in London as well as an animation lead for some shots. Bangalore supplied matte painting, compositing, rigging, modeling and roto. We used the full force of the MPC Arnold render farm to handle the bulk of the shots.
为 了达到这个效果，三维团队在模型控制上做了一些聪明的决定。这让动画团队能够完成小到面部表情的微调，大到巨型摇摆的动作。而要让（动画）模型做到这些只 需要添加一些非常简单的额外操作即可。我们考虑过添加一些诸如肌肉系统之类的效果，但因为我们只有4周时间去拍摄及后期制作，时间上实在吃紧。我们只能希 望通过动画以及模型控制上做出相应的创意性的解决方案。
以 导演的分镜图为基础，我们大致测定了恐龙在每个镜头里移动的距离和位置。我们决定恐龙将有5米左右高，11米长，在追逐模式下速度3.5米／秒。事先排演 如此巨大的角色在镜头中的位置是必不可少的准备工作。当我到达布景地时我手上已经有了一份半成品的拍摄照片，这避免了时间延迟的潜在风险。
马 克驾车带我去到拍摄地，布里斯班（澳大利亚第一大海港，昆士兰州首府，全澳第三大城市），也是他的故乡。因此我们用了一个半小时去了解彼此。在第一次会面 里我们大致讨论了一下他心里对于拍摄的想法，而他的想法是快速运镜，运用手持式摄像机或独脚架拍摄。就像镜头中的所有东西都能体现出自然光在一天中的变 化。因此我们需要移动光源，就像我们徒步在灌木丛中行走一样。
我需要为打光团队准备HDRI（High-Dynamic Range Image，高范围动态图像），以及拍摄照片做质地和纹理参考。
这 其中包括了暴龙的每个动作和他接近演员时的效果。在山岗上，导演、监制和剧组都在做一些简单的准备，让马克导演能更好地理解恐龙的动态效果。比如，在那个 吼叫的镜头里，其中一个道具师举着一块一米见方的宝丽板，制造出演员身上的遮光效果；而在恐龙靠近并吼叫的同时，在摄影机下方，镜头之外，另一个道具师举 着一个吹叶机，制造出强劲吐息的气流效果。这些方法简单而有效，既协调了动作又留下了空白的镜头空间。
我 们在得到了MPC全球工作室的鼎力支持，这需要监制和制作团队天衣无缝的配合。在上海我们的动画团队负责特效、打光、合成、视觉造型开发、调色和精剪合成 工作。伦敦工作室负责指导打光和部分镜头的动画工作。而在印度的班加罗尔则提供了背景绘图、合成、关节牵引、建模和动态抠图准备工作。绝大多数镜头由 MPC工作室的Arnold渲染系统的全功率渲染。