It's funny, I think of DK-50 as a really harsh-working developer. My folks have used it in deep tanks for 4x5 sheet films (mostly Ektapan, Tri-X, Plus-X) for as long as I can remember. The stuff can stand in the tank covered for ages, then come right back to life with a little fresh stock or DK-50R replenisher added. It's faster than developers like D-76: I seem to recall that development times for most films are only around 5 or 6 minutes at 68 degrees, with agitation at 1-minute intervals.(posted 8481 days ago)But it's not a fine-grain developer. Though great for sheet film, I suspect it would yield coarse results on smaller formats (which might be a nice effect, if that's what you're after!) I never actually tried it, though. But we souped some outdated 6x9 Tri-X in my dad's tank just last year, and got nice punchy negs...