Digital cameras are versatile and can be set to automatically select the best settings for most situations to ensure that the photos you take are of the highest possible quality. However, in some cases they can have trouble selecting the correct white balance setting.
Gimp: Course for Beginners 10: Correct a Color Cast with Color Balance
GIMP — short for GNU Image Manipulation Program — is an open-source image editing software program that allows you to correct white balance relatively easily.
Most light appears white to the human eye, but in reality different types of light, such as sunlight and artificial light, have different colors. Digital cameras are sensitive to this.
If a camera has the white balance set incorrectly for the type of light it is capturing, the resulting photo will have an unnatural color cast. You can see this in the warm yellow cast in the left photo above. The photo on the right is after the corrections explained below.