Frustum: Overview
In graphics and cinematography, a view frustum is the truncated pyramid defined by a camera’s field of view, near/far planes, and aspect ratio. Everything inside is potentially visible; everything outside can be culled for efficiency. In virtual production, understanding the frustum directly impacts how LED volumes refresh content and how set extensions are staged.
Practical Relevance on LED Stages
LED controllers and engines render high-resolution imagery only within the tracked camera’s frustum (“frustum window”), reducing GPU load and panel artifacts outside the cone. If the camera whips or the operator reframes quickly, late or misaligned frustum updates cause parallax errors or reveal low-res backgrounds. Camera/lens calibration, prediction filters, and genlock keep the window glued to the image.
On-Set Blocking and Lighting
Knowing frustum boundaries helps art and lighting: physical set pieces should extend beyond the edges to prevent revealing bare stage; spill from panels should be controlled to avoid lighting objects just outside the view. Assistant directors place background action to survive reframes without overpopulating areas the audience never sees.
Post and Previs Considerations
In previs and techvis, frustum overlays guide lens selection and coverage plans, ensuring VFX teams build only what must be seen at final pixel detail. Editors can evaluate whether a planned cut will cross frustum gaps that demand costly CG fills.
Troubleshooting and Tips
- Keep near plane conservative to avoid clipping foreground props.
- Verify lens distortion profiles; an incorrect profile warps the virtual frustum and breaks alignment.
- For multicam shoots, test frustum handoffs so background continuity survives angle changes.
Frustum: Related Terms
- Culling, nDisplay frustum window, genlock, lens mapping.