I was wondering about the feasibility of certain approaches to making full sized negatives for alternative processes that call for them. The starting point is an existing 35mm color negative. The easiest analog approach would be to put the negative into a slide copier, and shoot it onto black and white negative film. Hopefully this would create a black and white positive that could be enlarged onto large film for the final negative.

Has anyone done this before? Is the orange mask of the color negative of concern/should I add cyan filtration? I realize there is some experimentation to be had, but am interested in others' thoughts/ideas.

An alternative would be to make a color slide, eg using ECP-2 color print film, but this involves additional expense. And if then making a negative from it onto anything but panchromatic film, there would be color shifts.