Donald Qualls
Subscriber
In my experience XP2 does not have an orange base coulor. I have developed in C41 and B&W and apart from a slight magenta cast to the film base on some occasions it is otherwise quite clear.
Exactly. You have to replace that orange mask with enlarger filtration to get correct white balance if printing XP-2 Super on RA-4. It's one and done, though -- find the right filter pack, and you don't have to mess with it as long as you're still in the same batch number of RA-4 paper, and you'll need only minor adjustments in a new batch of the same paper product.
Edit: That said, I don't know why a home darkroom worker would want to print XP-2 Super on RA-4 -- it prints well on B&W papers, allowing you to work under appropriate safelight instead of in total darkness or the very dim amber safelights some workers use for RA-4.