Make Way For Goslings - Finish's Harin Hirani talks about creating their latest spot.
Please tell us a little about Finish and yourself.
Here at Finish we provide 2D and 3D visual effects and Colour grading across advertising, film, music and TV. We have an incredible bunch of people across the different departments. Jason Watts, owner of Finish, was the creative director on this particular project. Kayley Fernandes was the lead Nuke artist and I was the lead 3D artist and supervisor. I am a senior 3D lead artist at Finish, a generalist covering all areas of CG but specialising in look development and lighting. I joined 8 years ago as a junior where I helped out with modelling and texturing an alien creature. Prior to that my background and main interest was in art & design and photography. I completed an art foundation course and did a degree in computer animation where I was first introduced to Maya. My first bit of 3D involved texture mapping a sphere and rendering it with a directional light to create the planet Mars. Even though it was so simple I was blown away at how real it looked and it got me really excited about the possibilities of CGI. Since then I have developed a particular interest in photo-real creatures; the whole research and development aspect is fascinating as you get to learn new interesting things about nature which never fails to amaze!
What was the original creative and technical brief for the spot? Were there any big surprises that came up in preproduction?
The original brief was to create photo-real goslings (baby geese) aged about 3 weeks that represent the phone networks coverage. They needed to look and behave in a believable manner. The directors Si & Ad were very keen on us approaching the creation of the goslings as if they were shot in camera. Very early on in the project we decided to put together a reference document of the size and look of the goslings for the advert and built a master model based on this. However when it came to integrating them into the plates we had to cheat the scale of them in a few shots as even though they were correct most people tend to have a perception of goslings being much more dainty like ducks.
What were the core challenges with lighting and shading on the goslings?
I would say the core challenge for this particular project was to make the goslings look as real as possible and integrate the goslings into the plate convincingly. We built up as much of the surrounding environment as we could and used the colour information from the HDRI to light and shadow the goslings. All the lights were painted out from the HDRIs and replaced with physical area lights to provide more accurate lighting. We had to tweak the colour of the goslings in each environment as well because the colour temperatures of the lighting varied a lot and it made more sense for continuity that goslings looked more consistent over the whole advert.
I wouldn't say any particular new techniques were developed but having recently completed another big creature job featuring a beagle it was more a case of taking what we had learnt from that project and refining and improving the whole process. I used Mari to do all the texture work and the latest version has the aiStandard shader built in so it was great to be able paint texture maps like the specular and get a visual representation of how it would look once rendered in maya. The maps were done at 4K resolution across 4 UDIM tiles which meant we didn't have to worry about any loss of detail if we had to do extreme close ups.
Which Arnold plugins did you use for Goslings, MtoA, HtoA etc?
All the lighting and rendering was done within Maya so we were using MtoA version 22.214.171.124 with v126.96.36.199 of the Arnold core. We are aware Solid Angle puts a lot of emphasis on speed and efficiency when developing each update of Arnold so we are always keen to upgrade our machines and render farm before major jobs so we can reap the benefits when it comes to render time.
How large was the look-dev & lighting team on this project?
Just me! Because we had a fair amount of time to complete the project we had a relatively small team of people on the project. I was able to concentrate solely on the build and look development of the goslings and set up all the lighting for the shots. The look of the goslings was being tweaked right up to final renders such as the wetness of the feet and the fluffiness of the fur.
Was motion-blurred fur difficult to render in Arnold?
Not at all, we do all of our motion blur within the renderer and there were a number of shots with a lot of fast movement. We were even able to increase the camera samples all the way up to 16 for these shots and still have very comfortable render times!
Did you stick to rendering into complete beauty passes or were a variety of AOVs employed to achieve the final look?
We always try and get the beauty render to be as good as we can coming out of the renderer minimising the need for major adjustments within the compositing software. So we were mainly rendering beauty passes with custom ID AOVs to isolate different parts of the goslings for colour correcting. Everything was rendered as Deep EXRs which meant we didn't need to render the goslings with any hold out geometry. This was especially useful for the tickling shot where we could make adjustments to the hand geometry and deep merge it with the gosling to have the finger bed into the fur in the compositing software without the need to re render the beauty.
How many hairs per bird, and how many control points per hair?
Each bird had 2.5 million hairs with 8 segments per strand. So that’s roughly 12.5 million hairs for a shot that featured all 5 goslings in 1 frame! We used Yeti for the gosling's fur.
What were the average render times, and on what CPU specs? Was rendering done in the cloud or locally?
The render times on this particular project for the main beauty passes ranged from about 10 minutes for the wide shots and 50 minutes for the close ups. We were mostly rendering with the latest machines on our local farm which have 2 x Intel Xeon E5-2650 20 core processors at 2.3GHz with 62.8gb memory.
Any other tips or thoughts for lighting and rendering artists working on similar characters?
Whenever working on characters especially photo real creatures it's important to find as much visual reference as possible. You really have to analyse every part of the creature and for shading how it responds to light. When you’re working on your shaders try to build in as much variance as you can into the texture maps and always include some subsurface scattering to help the character look fleshy. When trying to integrate your character into a live action plate it's important to get as much information about the surrounding environment as possible. Take HDRIs and use these to help you recreate the lighting setup used on set. Sometimes matching the on-set lighting isn't enough and that's when you can add extra creative lights. Having something on set similar to the character is really valuable as well. It takes away some of the guess work and gives you a visual target to aim for.