Definition

The whitepoint is a color that is defined for each image as the normal “white”.

Depending on the light(s) illuminating the scene, the whitepoint can be different.

Typically, the whitepoint follows a line in the Color space that represents the colors emitted by a black body at different temperatures.

It is hence expressed as a temperature in Kelvin

Can whitepoints be outside of the black body colors ?

Why are some whitepoints blue when a black body cannot be blue ?

What is the green/magenta setting and is it related to the whitepoint ?

What is the whitepoint used for, other than changing it to adjust the "temperature" of an image ?

Sources