Vero 4K flat colours when sending to 709 4k projector

Ok… And no HDR. So, there is no resolution downscaling happening like mentioned in some of the above threads, but the rest is more or less relevant (HDR → SDR/bt.2020 → bt.709 conversion and bitdepth conversion).

This is one thing related to bitdepth:

This means that any video that is a 4K UHD rip with bt.2020 colorspace and 10-bit HDR would be converted to 4K bt.709 SDR 8-bit, if the TV/projector can’t handle either bt.2020 or 10-bit.
So, there’s a conversion of HDR → SDR (bt.2020 → bt.709) happening as well as 10-bit → 8-bit. Sam is aware that bt.2020/10-bit and bt.709/8-bit are two sets linked together atm. That might change with some work in a future update (and might resolve some issues: e.g. bt.2020 8-bit or bt.709 10-bit output would be possible then).

Conversion of bt.2020 to bt.709 isn’t standardized and therefore not always perfect:

So, obviously the way conversion of HDR (bt.2020) → SDR (bt.709) can be done is limited and not something that has been standardized. All conversion has to rely on trial and error/a compromise and the results may vary from source to source.

Conversion will happen as soon as your TV/projector can’t handle HDR/bt.2020/10-bit atm:

So, what you experience should be exactly what has been discussed before as this conversion isn’t standardized nor is it always perfect with any given source file. There might be some improvements coming some time in the future though (so you can tweak the conversion a bit to your liking):