About a year ago, I tried very hard to track down Bill Anneman, who ran Perfection as a cottage industry on and off through the 70's and 80's, but had no luck. That was the one developer that made Tech Pan a usable option for me (EI 80 with very smooth scale), and I gave up on it after XR-1 was no longer available. IMHO, Delta 100 in XTOL is comparable in quality, so it doesn't bother me much anymore. Good luck!(posted 8463 days ago)