There are a few questions here that need to be addressed:
- What is a color cast
- How does it occur
- How do you fix it
- Do you need to fix it
What is a color cast?
A color cast is just when the picture’s color is off. It may be on the yellow or blue side. A good way to see the color cast is just to look at the skin tones or white clothing.
How does it occur?
If you take a picture when the sun is setting there is generally a warm/yellow color cast. If it is a really overcast day, you may have a blue color cast. If you take pictures inside under tungsten lighting, there is a yellow color cast, or if you take pictures inside a green tent on a sunny day, your children look like little aliens.
How do you fix it?
The first step is to set the white balance in your camera. White balance is a little misleading since your camera is looking for 18% gray tones. With DSLR cameras, you can use a grey card to set the white balance for your specific situation. Basically, you buy a grey card (you can find one in any online photo store), take a picture of it, then select that picture in your camera’s white balance menu. Then start shooting! Each camera is different, so look at your manual as to how exactly it works for that brand.
To be honest, I am lazy and haven’t done that. I have a grey card, I know how to set it to be custom, but I’m just plain lazy. It seems like most situations I can use the white balance presets in my camera and they give a pretty good color balance. If the light is changing a lot, say if you are outside and it is a partly cloudy day, then I use auto white balance. Using a grey card would be too cumbersome and not quick enough for that type of situation.
If the color is off a lot, then I fix it in Photoshop. In CS2/CS3 you can use an adjustment layer for color balance and in Elements you can go to Enhance -> Adjust Color -> Color variations.
I normally find that I have a yellow or red cast. Nikon tends to veer to the red spectrum. How I really look at whether the color is true or not, is the skin tones and if there is anything white in the picture. I will move the color changes around until I get what I know to be the true colors.
Do you need to fix it?
Now, if you want something with a warm color cast, just leave it. You can take artistic license to not make changes, but I think you should really look and know when a photo has a color cast to it. When you are trying to get pictures that portray how your subject truly looks, then you need to know how to fix the color.
For instance, if your daughter has porcelin skin, you don’t want her to look like she’s been sitting in the tanning bed for two days straight. That’s when it is a good idea to fix the shot. 😉
I post photography and Photoshop tips (nearly) every Saturday, so check back for more or browse my archives under Photography Tips. I’m open to content suggestions, so if there is an area you are interested in, just leave a comment.