- Sep 26, 2003
- Color Essentials
- Identifying a Color Cast
- Understanding Color Correction with Image Variations
- Mimicking the Color Darkroom with Color Balance
- Global Color Correction
- The Numbers Don't Lie
- Selective Color Correction
- Alleviating Extreme Color Problems
- Correcting Color Temperature Problems
- Interchannel Color Correction
- Closing Thoughts
Identifying a Color Cast
The color correction process always starts by identifying the color castyou have to know what the problem is before you can apply a solution. Color casts, also referred to as a shade or tinge, are easier to identify in lighter image areas, such as a white shirt or wall or in neutral areas. For example, a gray sidewalk would be a good place to look for a color cast. When evaluating an image for color, find a neutral reference, something that should be white, near white, or gray. If it looksfor discussion's sakeslightly blue, then you know that the image has a blue cast. Interestingly enough, clearing up the color cast in the lighter and neutral areas usually takes care of most of the required color correction work throughout the entire image.
The tools used to identify a color cast are your visual memory, the Info palette, the individual image channels, and practice. Color casts that are similar, such as blue and cyan or magenta and red, take a bit of practice to identify correctly. If you have a color cast in your highlights, nine times out of ten you'll have a color cast in the entire image. Just because color casts are harder to see in dark areas doesn't mean that they're not there. Once you have identified the color cast, think globally and take care of the general color cast problem first. Thankfully, correcting the big problem usually takes care of many of the smaller problems along the way.