I've noticed that adding contrast, and darkening warm hues tend to pull colors towards red. I love dark red hues, but I've been wonder what caused this. I had my doubts whether it was a visual illusion, so I put it to a test in Photoshop. Lo and behold. According to photoshop's color science, hues do pull towards a reddish hue when darkening. This test is by no means scientific. And image compression as well as web compression will certainly make the results even less scientific. But visually the results are pretty close. What are your theories? Limited color space with automatic gamut remapping?