iPhoto ’11: The Macintosh iLife Guide to using iPhoto with OS X Lion and iCloud

Custom White Balance

Most cameras also let you create a custom white-balance setting. Generally, the process works like this: put a white sheet of paper in the scene, get up close so the paper fills the viewfinder, and then press a button sequence on the camera. The camera measures the light reflected from the paper, compares it to the camera’s built-in definition of white, and then adjusts to compensate for the lighting.

If you’re a stickler for color and you’re shooting under strange lighting conditions, creating a custom white balance setting is a good idea.

Better still, shoot in raw mode if your camera allows it. Then you’ll have complete control over color balance.