CleanPlate

CleanPlate is a pre-keying tool in Fusion that prepares a green- or blue-screen image for DeltaKeyer. It builds a technical screen-only plate for the keyer to compare against the original frame; it is neither a standalone keyer nor general-purpose object removal.

The clean plate is most useful when screen lighting varies across the shot: darker corners, soft shadows and local color patches. Its purpose is to give the keyer a screen reference without hard-clipping the subject’s fine detail.

Use two parallel branches from MediaIn or Loader: one to CleanPlate.Input and one to DeltaKeyer.Input. Wire CleanPlate.Output to the dedicated magenta DeltaKeyer.CleanPlate socket, then DeltaKeyer.Output to Merge or MediaOut. MediaIn → CleanPlate → DeltaKeyer.Input is the wrong routing.

Inspect CleanPlate.Output directly before connecting the keyer. The screen should form a consistent green/blue reference, with people and props excluded as gaps at intermediate stages. Those holes are not proof of failure; Grow Edges and Fill are meant to propagate surrounding screen information.

Method = Color works best for fairly even screens. The archived Plate screenshot shows Color, a Background Color picker, Red/Green/Blue and Threshold. Sample representative screen pixels, avoiding skin, hair and specular highlights.

Method = Ranges is designed for screens with mixed shades and shadows. The manual describes channel/luminance ranges, Lock Color Picking and Reset Ranges in this mode. The two archived PNGs do not show the opened Ranges panel, so its exact current layout must be confirmed in Resolve.

The saved Inspector displays Red/Green/Blue = 0.5; that is merely the captured swatch state, not a suggested green-screen preset. Sample the real screen and inspect the RGB Viewer result.

Matte Threshold has Low and High. In the documented intermediate matte, values below Low become black/transparent, above High become white/opaque, while values inside the interval are graded. This intermediate matte is not identical to the final subject alpha produced by DeltaKeyer.

The screenshot shows Threshold Low=0.0 and High=0.75 as captured values, not universal settings. Inspect the selected screen first, then adjust gradually. Excessively loose selection can admit subject detail; too strict a selection may leave holes.

Erode contracts the accepted screen area to reject small non-screen color regions at object boundaries. In the manual this operates on the pre-matte, not the final keyed hair. Too much Erode can remove useful reference pixels.

Crop trims the source area at Left, Bottom, Right and Top. The archived inspector has this section collapsed; the directional fields are documented in the manual but not visible in the screenshot. Use it to exclude distant regions that would distort screen reconstruction.

Grow Edges propagates nearby clean-screen colors into excluded gaps; Fill completes remaining holes using surrounding screen colors. Establish a sound pre-matte first, then grow and compare Fill on/off. Neither control reconstructs the actual scene hidden behind an actor.

Time Mode = Sequence regenerates the plate each frame, whereas Hold Frame retains a single frame. The better choice depends on motion, lighting changes and shadows. The PNG shows both options but no dedicated held-frame picker, so do not invent one.

Garbage Matte is a dedicated input for excluding a subject, boom or other non-screen objects from plate construction. The Mask tab offers Invert, changing which side of the mask clears the plate. Check black/white polarity in Viewer before switching.

Effect Mask is a third, blue CleanPlate input, distinct from the white Garbage Matte: it gates the processed result rather than excluding non-screen areas during plate synthesis. The manual documents both inputs; the archived PNGs cover Inspector only, so verify physical positions in live Flow.

DifferenceKeyer solves a different problem: extracting differences between background and foreground frames. CleanPlate is primarily a chroma-screen preparation tool for DeltaKeyer’s Clean Plate socket. Do not replace the correct DeltaKeyer branch with a superficially neat serial chain.

Test several consecutive frames. On CleanPlate.Output check screen uniformity and holes; on DeltaKeyer.Output inspect hair alpha, semitransparent edges and remaining green/blue spill. Change one variable at a time and compare bypass states.

Actual results depend on capture and color management. Keep the same linear/gamma handling, gamut, Viewer zoom and compare point. This article does not promise particular pixels or speed gains without a native DaVinci Resolve test.