I have lots of shots of coloured ink in water on a white background.
I've cut them together but the whites are all slightly different.
I have tried to change them with the colour corrector and colour corrector 3-way but they are still not consistent.
Is there another way (preferably) in FCP or apple colour to make sure all the white backgrounds are the same white value?
Sounds like an exposure or color balance problem when it was shot. Like the camera as on auto. You can probably white balance it in FCP with the three way color corrector. Use the eyedropper on the lower left of the white color hub to suck up what's supposed to be white. You'll probably have to tweak it after that.
All the best,
Class on Demand DVDs "Complete Training for FCP7," "Basic Training for FCS" and "Final Cut Express Made Easy"
Author: "Final Cut Pro 5 Editing Essentials" and "Final Cut Express 4 Editing Workshop"