Are you using Xorg or Wayland? One possible source of problems could be Wayland still not handling colors. Another possible test is to use rec 2020ncl (with RGB-FLOAT and 10-bit color depth) instead of rec709 or 601, because it is definitely with wide gamut colors (But the color range is still limited; from 64 to 940). True that the color range of bt 709 is “limited”; from wikipedia: "Rec. 709 defines an R’G’B’ encoding and a Y’CBCR encoding, each with either 8 bits or 10 bits per sample in each color channel. In the 8-bit encoding the R’, B’, G’, and Y’ channels have a nominal range of [16..235], and the CB and CR channels have a nominal range of [16..240] with 128 as the neutral value. So in limited range R’G’B’ reference black is (16, 16, 16) and reference white is (235, 235, 235), and in Y’CBCR reference black is (16, 128, 128) and reference white is (235, 128, 128). Values outside the nominal ranges are allowed, but typically they would be clamped for broadcast or for display (except for Superwhite and xvYCC). Values 0 and 255 are reserved as timing references (SAV and EAV), and may not contain color data (for 8 bits, for 10 bits more values are reserved and for 12 bits even more, no values are reserved in files or RGB mode or full range YCbCr digital modes like sYCC or opYCC). Rec. 709's 10-bit encoding uses nominal values four times those of the 8-bit encoding, to ease the conversion it uses simple padding for reference values, for example 240 is just padded by two trailing zeroes and gives 960 for 10 bit maximum chroma.[22] Rec. 709's nominal ranges are the same as those defined in ITU Rec. 601.[23]" User DeJay did tests that are shown here at the bottom of the page: https://cinelerra-gg.org/download/CinelerraGG_Manual/Color_Space_Color_Range... PS: I would like to ask how long moderation lasts for a new user. It is now more than a week (with 7 posts) that Tarantas has been registered...