You are using HDMI output to your PC-monitor, you are likely not getting a full and accurate color range, especially at the black and white ends of the spectrum. The colors look "washed out".
When using HDMI, GPU Vendors assume there is a TV on the other side and default to "Limited RGB" (= 16-235 levels of differentiation between colors, designed for TV's) and as long as there is and both sides are using the same setting - everything is fine.
The problem arises when you are actually using a PC Monitor which supports "Full RGB" (= 0-255 colors).
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Resolution
When switching to "full rgb" you will benefit from deeper black and brighter whites, which is especially important in the high contract situations we have in X Rebirth. How to do this depends on your GPU vendor.
For NVidia
Right-click on your desktop and select "NVidia Control Panel". Select "Change resolution" and select your display.
If you are suffering from "Limited RGB", your display will have the resolutions listed under "Ultra HD, HD, SD" ( instead of PC ).
Select the resolution marked as "native". At the bottom you will now see several options:
- Desktop color depth which should be 32-bit
- Output color depth
- Output color format which should be RGB
- Output dynamic range, which is "Limited" ( by default ) and should be changed to "full".
Then click on apply.
For ATI
Open the AMD Catalyst control panel.
Switch the desktop to 1080
Go to My Digital Flat panels and change the pixelformat to "RGB 4:4:4 Pixelformat PC Standard (Full RGB)".
Switch your desktop back to native and the pixelformat-setting will remain.