jeljohns wrote in post #15244060
I get that I should do custom white balance, but doesn't that only balance one light source?
Doing a "custom white balance" setup will (assuming the light has a full range of colors in it) create a "proper" balance for the light that fell on the test target. If all of the light (from different type sources) that is falling on the scene is equally mixed and the test shot was using light representative of that falling on the whole scene, then the results are what one would expect when using a "custom white balance". However, if one portion of the scene is illuminated by flash and another portion by incandescent lights and another portion by some other light source, it will be quite impossible to get the camera to make the whole scene look as if it were lit by the same type of lighting.
As mentioned above, the solution is to gel one or more light sources so that ALL the light sources appear to be the same color. Then, and only then, one can make a single color correction (either in the camera using "custom white balance" setup or in post-processing) and get the whole scene corrected and looking the same.