BW fixer in color process?

Today while experimenting with an old E-4 processing kit I got some time ago, I compared the clearing time with the E-4 fixer to that of fresh TF-5. The TF-5 cleared my film in about 40 seconds while the E-4 fixer required over five minutes. (The kit's prehardener was DOA so I am processing at room temperature.) Can a regular B&W rapid fixer such as TF-5 be substituted for the prescribed fixer in a color process?

For experimentation, usually you can substitute them well enough. Acidic fixers may have negative effect on dyes, still I have used Agfa Agefix for color materials without apparent problems, however I can't say about long-term dye stability. Neutral pH fixers (or only slightly acidic or alkaline) are very close to color fixer formulations. I'd bet that TF-5 works well! (But it cannot be guaranteed.) However, just to be sure, usually the substitution is recommended the other way round -- so that you can use color fix for BW material.

And, you are probably aware that for old color films, you need formalin in final rinse for dye stability.

Seeing as how it's old E-4 film, I doubt there will be any long-term color stability regardless of the materials used. I'll be happy if my transparencies stay clear long enough to copy onto E-6 film and to scan. And yes, I do have the formalin stabilizer. That may be the single worst smelling chemical I have ever handled.

Color processes require a near neutral pH fixer. TF-5 is near neutral. It can be used for E4, E6, and C41 in a pinch.

PE

Excellent, thank you, PE.