Relight

Relight operates on a 2D frame. Orange Input accepts RGB, green Normals accepts an external surface-direction map, and blue Effect Mask limits application of the effect itself. These are not scene3d, material or a light source for Merge3D.

Use Internal builds Surface Map inside the tool. Output Surface Map makes it output the colored technical map, which can feed the green Normals input of a second Relight set to Use Normals Input. The second tool also needs the source RGB from the same frame.

With Relighting Map Preview disabled, the main RGB remains the source image while alpha carries that light’s mask. Enabled Preview reveals the mask’s influence. Brightness changes its influence on grading; it does not replace a color tool’s Gain or Gamma.

The documented Fusion setup separates the source, color grade and Relight mask. In the teaching graphs, Bitmap with Channel=Alpha explicitly converts image output to a Merge mask. This makes the carrier and selected channel visible without an implicit connection conversion.

Directional, Point Source and Spotlight are the three modes shown in the PNG and documentation. Spotlight creates a light cone; these sources show no fourth Cone button. Direction, position, beam angle and softness controls depend on the selected mode.

Surface Map describes orientations rather than physical object distances. Relight does not calculate full scene geometry, recover a depth pass or create mutual cast shadows between objects. Shadow Softness controls approximate light penetration into dark areas.

A saved or reused Surface Map must match RGB in frame, size, crop and transform. External applications use different normal formats; test Rescale and Reinterpret on an object with clear curvature and light direction.

Effect Mask is applied after tool processing. Do not assume it automatically multiplies the extracted alpha mask: blending the source RGBA may also change alpha outside the region. The local exercise masks the separate color tool while lighting alpha feeds Merge.