Keeping things simple, the white balance of a digital camera affects how colors appear in photos. Most light appears white to the human eye, but in reality, different types of light, such as sunlight and tungsten light, have slightly different colors and digital cameras are sensitive to this. The result is that if a camera has its white balance set incorrectly for the type of light it is capturing, the resulting photo will have an unnatural color cast. You can see that in the left hand photo on this page, that has a warm yellow cast. The photo on the right shows it after the corrections that are demonstrated on the following pages.
Serious photographers will proclaim that you should always shoot in RAW format because you are able to easily change the white balance of a photo during processing. If you want the best photos possible, then RAW is the way to go, but if you're a less serious photographer, the necessity to also undertake the other steps in processing can make RAW more complicated and time consuming. That's because when you shoot JPEGs, your camera automatically undertakes a lot of these processing steps for you, such as sharpening and noise reduction.
Manually sharpening and reducing noise using GIMP and other image editors is relatively straight forward, however most users do not consider it so easy to correct the white balance of JPEGs. In the following few pages, I'll show how a few simple features in GIMP will help you to correct white balance to achieve impressive results. These steps will also help you to understand how the Levels tool and Color Balance and Hue-Saturation features operate.
• What is a digital camera raw file?
• White Balance in Photography
• Color Temperature in Photography
