I tried for a couple of years. I combined and modified 2 formulas that had been published in days gone by in the old Darkroom and Photo Techniques magazine. I bought and maintained ph meters etc. All dry chems. There is a wild card chemical in the mix that I never did get a handle on and every time I thought I had a good repeatable formula.........I really didn't. I'm enjoying black and white and hate to admit it on this forum but the better the little digi cams get the farther I get away from doing anything wet color again.