Originally Posted by DavidinGA
Why does it look less color-rich when I output in BT2020 format (via calibration in madVR) though?
When you tell madVR that your display is calibrated to BT.709, madVR remaps all the colors in the video output to match up to BT.709 color coordinates on the visible color spectrum.
If you then set your display to BT.709 color space, all the colors will display correctly since the output format and the display format match color spaces and match color coordinates.
If you set madVR to BT.709 and then change your display's color gamut to BT.2020 all the colors will appear over-saturated and incorrect. This happens because the the color coordinates in the wider BT.2020 gamut are farther "out" on the color spectrum at more saturated positions.
Setting madVR to BT.2020 means that madVR will map all the colors from the source into BT.2020 color coordinates. If you set your display to BT.2020 color gamut then all the colors will display correctly.
If when you have madVR set to BT.2020 and then set your projector to BT.709 color space, you will then see under-saturated and incorrect colors. This happens because the the color coordinates in the smaller BT.709 gamut are farther "in" on the color spectrum at less saturated positions.
What's important is that you simply match up the color gamut setting in madVR with the color gamut mode you are using on the display. Either set both to BT.709, or set both to BT.2020.
Every display you can set both to BT.709 and color will be correct, though you will be giving up some of the wider colors that may be found in HDR content
On a display that is capable of displaying a wider color gamut than BT.709 (like DCI-P3) you should set both to BT.2020. This will take advantage of the wider color gamut that the display is capable of showing when playing content that actually has colors encoded in that part of the gamut (HDR content).
It's difficult for me to explain how different color gamuts will map colors without me knowing how much you understand about how gamuts work in general.
But to recap.
Setting the output and the display to the same color gamut will produce the correct color saturation.
Setting the display to a wider color gamut than the output will produce over-saturated colors.
Setting the display to a narrower color gamut than the output will produce under-saturated colors.