Looks like I lost my enlarger lenses on the move but found an 8x10 Nova processor...not the new one, the old one that fits into something that looks like file folder holders that resides on your desk. Anyway, just wanted to do quickie contact sheets, Ilford postcards, and RC prints on it. Looks like I have the chems to make d72. Anyone use it before? My 8x10 Nova's take 1 liter each of chems so I'm guessing...about 1:1 or 1:2? That would be only about 300 or so stock solution + H20. How long would that last?