Thank you for your article Sandy. I have been struggling to find an ideal developer for sheet film for a while. I use Fortepan 200 in 8x10 and have tried it in D-76, DK-50, HC-110, ABC pyro and Rodinal all producing good, but not great results for enlarging. I have tried PMK in 120 a few years ago and loved the sharpness but could not stand the muddy highlights it often produced with vc papers. Graded papers were fine but not readily available here in Australia anymore.
Yesterday I decided to mix up some Pyrocat-HD and processed some test sheets of 8x10 Forte 200 rated at EI:100 for 16 minutes at 20 degrees. The results were fantastic. The rich brown stain noticably different from that of PMK. I enlarged a small section of the neg about the size of a 120 neg up to 8x8 inches. The sharpness and lack of visible grain is quite incredible. Highlight tones are silky smooth and luminous whilst the midtones are rich with excellent separation.
It appears that I should be able to make enlargements from 8x10" negs up to 30x40 inches in size without a problem. This is exactly what I have been looking for.
Thank you so much for the work& time you have put into researching & publicising your formula.