George Quelch - VFX

A side to looking into Volumetrics in Nuke I have been exploring the Depth to Points node. It's a very clever workflow that only needs a depth and normal pass, which allows you to project your render out into 3D space within Nuke. This process would save having to export geometry and cameras out of Maya, it would all be self contained within the render and the passes, which I thought was really interesting and convenient. To give this technique a test I decided to composite in a sphere into the background of the shot. This is what I was able to produce. Which considering was all done in Nuke without and interaction after render with Maya is pretty cool. I was able to position the sphere within the projection, then by looking in 3D space was able to match where the lights were in order to quickly match the lighting on it. I also tested it with volumetric lighting, although this caused me a lot of trouble with matte lines around the table, I think ...

This week I have been looking into different render solutions for volumetric lighting in 3D. I have been working with Arnold to create some basic lighting with a previs model for the cave created by another student. It was only a quick render, whilst I felt this worked OK the volumetrics were quite noisy and added a lot to render time. I am confident with adding them into 2D space with Nuke but had not added them to 3D successfully yet, so they work with a moving camera, so this is what I wanted to look into doing with Nuke. I found a good toolset with the TX_3DRays gizmo from Nukepedia. This allows quick creation of a light shaft which you can positing within 3D space, by reading in the geometry I could also use it as a holdout so the volumetrics sit properly within the scene. Using two slightly different workflows I created the two images below, which have slightly different looks. I prefer this first image as the result is more subtle, and i...

Finally ! Renderman 21 for non-commercial is now out, meaning we can move into look development and lighting tests with Renderman for 3rd year films The Big Top and Dino Diner. I have been looking into it this evening, after downloading and installing it as fast as I could. I was pretty happy that old scenes were somewhat compatible. All I have had to change were the lights, but as I am focusing on relighting my kitchen scene anyway that was no problem, all of the shaders I transferred over to the new PxrSurface shdaer, which I am really liking. This version is far more user friendly than the last, but with all the power. I am also noticing a lot of the little things from Arnold which I like having coming across now into Renderman, which is great. The whole settings UI is much improved, now fully integrated into mayas render settings, its just far quicker to use and setup. One thing I am really pleased with are the new lights and lighting tools, I was keen to ...

I and several other students are working on a side project for Cherry Cherry VFX. We are creating a short cinema sting, featuring a photo-real seagull, floating on a lifebuoy in the open ocean, and an clapperboard jumping out above it. There was a lot to figure out with this project, mainly with the ocean as we need it to be simulated to create the splash, we need it to base animate the motion of the life buoy, and also be able to render it as a wide open ocean. My role is mainly to do lighting, rendering and compositing, and have been helping with pipeline, especially on the water simulation. Harry has been working with BOSS and Bifrost to create a workflow in which we can drive the bifrost simulation near the camera using a BOSS ocean, which means we can make the splash. But further away from camera will be a tiled version of the base BOSS ocean, without the simulation. We were struggling with long render times on the ocean as it is simulated and quite dense. We ar...

For look development on The Big Top I am continuing to look into cloth shaders. Again testing in Arnold. The idea behind this was similar to what I did previously with Renderman. Using maya's cloth texture which I adjusted to my liking, and used it for a bump on the model, which was simulated with nCloth. I also added the small XGen hairs to enhance the fuzzy effect, I think this worked well. One thing I want to look into doing with this is small bumps, and caught hairs you get across different fabrics. One thing I did differently was use several noise textures to get variation within the colour of the cloth, so it wasn't one perfect shade throughout. I want to get a better look development maya scene set up so I can work on things in better lighting conditions, also so it is universal between engines.

A big part of the pipeline I designed for The Big Top was using HDRs of the sets for lighting the CG characters. This makes the process of lighting the CG much smoother, and the end result will look better. We shot 9 exposures from 2 angles using a Canon 5D mkiii, and a 300mm lens.  One of the challenges with shooting HDRs for stop motion sets is the size, so we had to find a camera with a short enough focus distance to capture both angles in the small space, but long enough focal length to fill as much of the frame as possible. Once we had the images I used Photoshop's HDR Pro function to merge them into one single image which I exported out as an EXR. I then took this into Nuke, to do the unwrapping process, I did this  with the spherical transform node, which worked well. Obviously there is massive distortion to the left of the image, and to the right you can see where we were taking the photos, this is where the second image is needed. ...

For look development on The Big Top I have been working on shader tests for plastic materials, in both Renderman and Arnold, these first 3 are rendered with Arnold. We are taking reference from Evil Corp  who make great plastic style CG models that look very realistic. The key things I picked up on was the subsurface scattering, and the amount of specular on the skin, so before we get some models and textures I am experimenting with these properties on this model. I played with getting the scattering correct, which you can see working on the ear. I then played with varying amounts of specular and reflection. I don't think any of them are quite right yet, it will be easier to play with shaders once we have some textures painted. I do like Arnolds ability to add lights for specific attributes, for example subsurface scattering, although its not physically plausible sometimes you want that control to push an effect in specific areas, although this could probably be...

After finishing some very basic materials for the lighting challenge scene file I went back in to relight the scene from my first version. This time with a warmer, more daytime feel to it. This is the 2nd version of this lighting setup, which I am more happy with, I changed how the outside lighting came through the window, tweaked the indoor lighting and added volumetrics. All done with Renderman for Maya and composited with Nuke. I used a EnvDayLight for the lighting coming through the window, this really boosted my render times over the HDR in my first lighting setup, so I will focus more on using a collection of HDRs for different times of day rather than the dayLight. I'm pleased with the lighting and feel but the textures are letting it down somewhat, so I think I will take them out, or at least the ones I definitely don't need, so I can focus more on lighting. I based this render off of this image , using it as an indication for the feel of the look I wan...