Tuesday April 21 -- Grand Tour, AOVs, and Live in CG
17 Apr 2026Overview
Rendering for compositing is an important part of the workflow in visual-effects and animated films (and to a degree, but with a different process of multiple render targets, also real-time games). The point of this exercise is to learn more of the important concepts and process. Arbitrary Output Variables (AOVs) are essentially separate images and data packaged within an EXR file and have become the standard means of packaging this data for compositing (which you’ve used in the Nuke 101 examples and hopefully your previous project).
The renderer calculates a variety of information during rendering, and AOVs may be constructed using this data to create elements that are useful during compositing. The main pass (often called “beauty”) includes most of an overall look, but separate AOVs may contain shadow or reflection data, indirect lighting contributions, depth, motion, etc. Bringing this data into a 2D or more recent 3D compositing workflow allows a myriad of adjustments post-rendering, which can sometimes save time iterating to reach shot finals. Light-path expressions may also be setup to render specific lighting-related AOVs to give more flexibility in gompositing, and many studios combine lighting and compositing as the same final department before editorial.
Complete the following. A few questions from major concepts will be on Quiz 2 soon.
- Read this page, particularly on color workflow. Download the files and look through the Nuke composite tree within Nuke.
- Read this RM docs page on AOVs.
- Read this Arnold docs page on AOVs.
Also, for the “inverse” of our recent project 2, take a look at these videos setting up a person being placed in a GG environment: Part One and Part Two.