Ive been using pyrocat-hd for a couple of years now and have found it to be a great developer with good versatility, tonality, grain and generally fine results. My normal solution is 1:1:150 for most things, with the occasional semi-stand thrown in for good measure. It seems capable of decent results with many different films, traditional to tabular.

I continue to hear about people who have "tweaked" the numbers by varying the concentration with respect to parts A & B. For example, some folks use it with 1: 1.5: 150 or 1.5 : 1: 200. I know that changing dilution and agitation can affect development and grain, but could someone explain how this change in dilution of the A & B parts affects development? Does it change the actual film's curve at all, or does it simply change development time?

Thanks, a befuddled tim

P.S. I'm interested in people who have actually done these experiments, not in the cousin of a step-brother whose milkman knew a guy whose uncle was working in....