Gamma-correct Color Blending
This is what 8-bit color translucency usually looks like. As explained in some previous posts, the scene in this screenshot is a worst case scenario.
Now,
the same scene with brightness-correct & color-correct lighting, color-correct & gamma-correct translucency, gamma-correct per-pixel dithered quantization on mipmaps, and soft-depth transparency on blended liquids (the "glass" in this map actually uses a flat-colored liquid texture, which is why it's also rendered with soft-depth transparency).
Gamma correction on color blending makes the resulting image more smooth and colorful, avoiding saturation losses across different hues. This is actual gamma correction, based on the gamma scaling techniques implemented on computer monitor hardware.
Here's a practical explanation.
This was how it looked without gamma correction. The colors were more dull (as in the example from the link above), and less smooth (as can be seen in the wall at the right side of the image).