You can more accurately control color and prevent a color cast in a photo by selecting a user-defined white balance.
Many digital cameras have a Custom White Balance setting that is quite easy to use, though it may take a few minutes to get the hang of it.
Factory preset white balance settings work well in a variety of lighting conditions. However when lighting is mixed, custom white balance is particularly effective.
Use a white colored object
After selecting Custom from the white balance setting menu, point the camera lens at something white such as a piece of paper or white shirt. Make sure the item is held close enough to the camera lens so that only it appears in the viewfinder. If you do a lot of custom white balancing, you may want to purchase a special 18% gray card or a white balance lens cap.
Make sure the reading is taken near the subject, so the card is illuminated by the same light. The camera will take a reading from the white object and adjust the white balance to the lighting in the room.
Accessing and using the custom white balance feature varies from one digital camera to another, so check the manual for specifics. Take a few test shots after the custom white balance is set and check them on the LCD.
When shooting with the Custom White Balance is complete, don’t forget to switch the camera back to Auto White Balance mode. The custom setting is usually saved until the next time you change it.