Composite an isolated subject over a solid background colour straight out of export — no round-trip through a compositor just to preview or deliver a keyed plate. It uses the exact alpha your layer stack already computed; turning it on doesn't mean building a new matte.
Cut Out Mode lives in the Alpha section of the Output panel, right alongside the standalone matte sequence toggle. Turn it on, pick a background colour, and every clip that already has alpha enabled on at least one layer renders composited over that fill instead of left untouched — the same qualifier, shape, or Segment selection that graded the shot, just delivered a different way.
The composite happens in linear (ACEScg) working space, before the display transform and encode step — so the fill colour reads correctly rather than getting crushed or blown out by gamma. And if you're also embedding alpha in the same file, Transduce automatically switches that embed to Straight rather than Premultiplied, so a compositor downstream doesn't darken a fill colour that's already baked into the pixels.
| Combination | What you get |
|---|---|
| Cut Out alone | A composited RGB plate over your chosen colour — no alpha needed downstream. |
| Cut Out + embedded alpha | The composited plate, plus a Straight alpha channel in the same file for re-keying later. |
| Cut Out + standalone matte | A keyed plate and an independent travelling matte sequence, delivered together. |
Composite over a solid colour straight out of export — same alpha, one toggle.