My son, Randall is an avid scuba diver. He also enjoys underwater photography. He was recently reef diving off Cozumel, Mexico, and took the following photos.

Since photos taken underwater tend to have their color balance messed up, because water attenuates some colors more than others. Photos, without subsequent color manipulation, look too green. Most of these photos have their colors balanced, so they'll look natural to the eye.

It's a curious fact that color balance with underwater scenes looks okay to a scuba diver, but it's because his brain is "tricking" him. His brain recognizes that all about him lacks color balance, so it enhances the blue shades of images before the brain "sees" the image. But this trick is not performed by underwater cameras too, thus photos taken underwater require substantial color balancing. To fully appreciate this, see this underwater photo without color balancing,

and the same photo after color balancing,