FUEL VFX SPELLS IT OUT FOR GE

Published on Saturday, 10 September 2011

Fuel VFX worked with Director Graeme Burfoot, The Feds and Clemenger BBDO
Sydney to create GE’s latest brand campaign that shows off the company’s
innovations in transportation and business technology, health care and clean energy.
In this spot, a CT scan, a jet engine and a wind turbine come to life with the input of GE, represented by letters merging to form the machines. Graeme Burfoot wanted to express GE’s ‘imaginative thinking’ in an interesting, tactile manner.
Fuel’s VFX Supervisor Anders Thonell worked with the director, Writer Will Edwards and Art Director Chris Badger in pre production to ensure the visual effects elements were aligned with the GE brand story. He explained the steps taken in pre production to prepare for the work they would do in post.

Clear Vision
“We worked mainly from Graeme's detailed brief and sketches. We always offer previs in preproduction, especially for something this size, but Graeme has such a clear vision of what he wants that he can draw his own storyboards and the shots will match those very closely. We did do technical checks before shooting, measuring wind turbine heights for example so that we could brief the chopper pilot and DOP on how tall the structures would be. The plates they shot then reflect the correct scale for the models which we also build to scale.

“A lot of thought went into where the depth of field would sit in each shot as it was constantly used as a device focussing the action. We also decided to exclude G and E letters on signage so that there was less clean up in comp. On set, the camera team practiced moves on a real CT machine and then replicated this setup in the empty room where the plate for the animation was shot. Production also rolled on these practice moves and we used this as reference.
“Graeme’s sketches of the effects, which he does on prints of offline frames, were our main brief. But to save time we introduced a layout phase into our VFX work where we positioned and animated our completed models with and without flying letters. We then animated transparency textures across these models which cut away parts of the model to indicate to Graeme and Agency creatives which parts would be building when. This saved us a lot of trial and error in simulation as we used these same textures to drive the simulation stage which followed.”

Letter Menu
At the start of the job we worked up a palette of about 50 G and E font/letter choices to use as a ‘letter menu’. Every single letter in this job is driven by an image texture of a letter. This turned out to be crucial as font changes happened all the time and being able to just switch the texture and render gave us a lot of flexibility. Even on the big simulations we could change a font instance anytime.

Steve Oakley, part of a dedicated simulation team, designed software which plugged into Maya to drive the constructing machines. The simulation effects used in this commercial were complex and required not only that the letters merge and form in a naturalistic way, but that the ‘G’ and ‘E’ letters subtly evoked the correct message, colour and tone.
This system was able to ensure that the machines came together smoothly and also that the materials and lighting matched the completed machine at the point where they come to rest. It could even use Maya particle simulation at the front end of each letter's path, so that they could simulate a very wide variety of motion styles before the letters come to rest.
“To help viewers accept the idea of 2D print letters forming heavy, high precision pieces of machinery, Art Director Chris Badger wanted the letters to be as fine as the ink used to print them and to layer up like paper mâché to form the thicker surfaces of machines, which I think we achieved pretty well,” said Anders. “The letters that land on machine surfaces have the materials and texture defined by their end position on that machine. So that when they arrive, they fit seamlessly with the machine. The letters have no thickness, but we found that you can imply some thickness just by putting weight into the animation.

Natural Forces
“The letters had to be controlled enough to lock together to form solid surfaces but move freely enough to give a sense of floating on the wind which brings the machines together”, said Anders. “Graeme wanted all the movement to be justified by natural forces, wind or page flip and not by a contrived magic. Each shot had very specific requirements and he art directed most of them. But we also looked at leaves and feathers interacting with wind or a breeze to give us a sense of the kind of motion these letters would have.”
Fuel’s CG artists built replica models of the CT scan, jet engine and wind turbines, animated them and placed them into the shots. They had CAD files for the models which all had to be recreated from scratch, drawing on detail from photo reference to add or correct details. Anders generally finds this to be the case. CAD files can give you proportion and save a lot of time, but are not complete.

Transparency ramps were used to indicate which parts of the machines were constructing at any time and what the flow of the animation would be, which Steve used to drive his simulations. The ramps are greyscale textures of soft ramps from black to white, where black is interpreted by the renderer as transparent and white as solid, and were projected onto the models.

Cheat the Sun
They used HDRI generated from images taken on set to incorporate plate lighting into the objects in the simulation, manipulating them a little and adding lights to cheat the sun position. The weather wasn’t ideal on the shoot and a lot of work was done on plates and CG to introduce sun and warmth into the spot.

Almost every shot involves some hand-animated elements or unique treatment. “We’ve added character to the letters and multiple methods on almost every shot - key frame animation, particle and cloth simulations, proprietary simulations. This commercial has been a lot more hand-made than I anticipated, but it was necessary to get to that level of detail,” Anders said.
“Correct scale, tracking and layout were very important to make this project work in 3D space,” said Anders. “We rendered beauty passes which contained the entire simulation, including DOF out of Maxwell. Maxwell is a very physically true renderer. You have to set up your scene with layouts which are true to real world space and get your fstop and focus pulls right in order to match what is happening in the plate. The return was that we got beautiful bloomed defocus and a lot of subtle detail in the lighting.

Render Passes
“We rendered a number of matte passes to set apart different components of the simulation which we used in comp to enhance and manipulate the look of the beauty. For the compositors this becomes a lot like working with multiple live action elements for each shot and not the usual separate render passes to assemble. This puts pressure on lighting in 3D to get the look right and limits the flexibility in comp. It also requires experienced compositors to deal with these very finished passes. But we found that it paid off on this job and we were able to rework the look in comp using the various matte passes.”

Maxwell was chosen to render the spot due to the short depth of field that was used in-camera. They rendered with DOF in 3D in most of the shots. “The first step for our lighters on most shots was to put some simple shapes into the shot and animate the DOF to make sure it matched,” Anders explained. “Maxwell is also one of the few renderers that could handle the huge amount of geometry used to create this spot.” GE ‘Two Letters’ first aired in Australia on June 19. www.fuelvfx.com