More on Color Casts

Earlier I had written about "Gray Cards and Color Casts", and I feel I should expand on the issue of color casts a bit. While what I said about wanting the color casts caused by the different light temperatures we get during different parts of the day, particularly dawn and dusk, is true, at times the color cast is not pleasing to the eye and appears unnatural. Have you ever worn ski goggles? Without them the snow appears white and natural. Put on the goggles, though, and they look like the color of the goggle lenses, and very strange. After a few minutes your brain gets used to this color cast and reinterprets the color of the snow as white and natural. Take the goggles off and the snow looks wrong again until your eyes readjust. This is also true for unnatural color casts in photography, but the brain does not get used to it, at least not as easily. Instead, the picture just looks unnatural. The biggest effect of this that I regularly see is blue shadows. The blue of the sky is cast into the shadows. In the field the shadows look normal, but the image on screen shows the shadows as blue, sometimes quite blue. The blue light is really there, but it still does not look right. Warming this light will remove the cast, but sometimes this means double processing in Photoshop. More on that topic later. Another scene that will look blue when captured is white water, especially a long exposure scene with flowing water. Yet another scene is snow under a blue sky.

All of these color cast situations can be dealt with, but you have to look for them. Make two versions of an image at different white points and see which looks more natural. Play with the white balance. In the end you want to represent the scene, but also what you felt and saw when you were there, so try different settings. Often a shot looks just fine until you try something different, and then the original cast jumps right out at you.