Wanted To Talk About This For Quite A While
All the textures and model skins in the game were made with gamma 1 in mind, it's the only setting that keeps the original colors intact. Increase it just a bit, and the colors start getting washed out. Increase it some more and you get color burn artifacts, push it even further, and you've got ugly ass hard edges on all shadows.
It's a shit setting and you're better off just tweaking your display's brightness.
Quake 2 faced a similar challenge in how the game was too dark for normal people on a non-CRT monitor in a not pitch black room. But the awesome Yamagi source port fixes this by making the whole scene brighter, so you don't lose any color gradations.
vanilla Q2 brightness/gamma:
vanilla gamma behavior if upped:
Technical info about what Yamagi does:
* **gl3_intensity**: Sets the color intensity used for 3D rendering.
Similar to GL1 `intensity`, but more flexible: can be any value between
0.0 (completely dark) and 256.0 (very bright).
Good values are between `1.0` and `2.0`, default is `1.5`.
Applied in realtime via shader, so it does *not* need a `vid_restart`.
* **gl3_intensity_2D**: The same for 2D rendering (HUD, menu, console, videos)
* **gl3_overbrightbits**: Enables overbright bits, brightness scaling of
lightmaps and models. Higher values make shadows less dark.
Similar to GL1's `gl_overbrightbits`, but allows any floating point number.
Default is `1.3`. In the OpenGL3.2 renderer, no lighting fixes for water
are needed, so `1.0` has no special meaning.