The developers give very similar results. The color of the stain is quite different, which should matter some with VC silver papers. The major difference is that -MC gives slightly greater acutance in rotary processing, and oxidizes less with long development times. With most films times are interchangeable for the same contrast.
However, even though they give similar results -MC and -HD are quite different in terms of the chemicals in Solution A, more so than the slight difference in name would suggest.
Sandy King
Just tried Pyrocat HD on some FP4+ 120 format. I am pretty impressed. Is there a visible difference between Pyrocat HD and Pyrocat MC when we get to prints? Is there a measurable difference? I use rotary film processing and variable contrast paper. How about when I use either HD or MC on 4x5 negatives?
Thanks