Compositing

Compositing is the digital combination of multiple visual elements — live-action plates, CGI, matte paintings, particles, atmospheric effects — into a single seamless frame. It is the final visual assembly step of VFX work and the bridge between rendered or shot elements and the finished image the audience sees. Modern compositing is performed in node-based applications: Foundry Nuke (the industry standard for feature VFX and high-end episodic), Blackmagic Fusion (bundled with DaVinci Resolve), After Effects (motion graphics and lower-end VFX). Each operation — color correction, edge blur, transform, merge, defocus — is a discrete node in a tree, allowing non-destructive iteration and review. Compositing typically works in scene-linear color space using 32-bit float EXR files to preserve highlights and accurate light-additive math; values can exceed 1.0 to represent extreme luminance. The compositor handles roto (animated cutouts), keying (chroma key, luma key, despill), tracking (2D and 3D camera solving), grain matching, lens distortion matching, atmospheric integration and final color balance — every detail that sells the illusion that the elements were captured together. Pipeline-wise, compositing happens late in the VFX chain (after 3D rendering and matte painting) and feeds the master back to the editorial conform and final grade. Major studios standardize on USD (Universal Scene Description) and OpenColorIO to keep compositing consistent across vendors. Reference: VES Handbook of Visual Effects and the Foundry Nuke documentation.