Hi Roger, with Tri-X 4*5, I've recently been using Rodinal 1:25 @ 68 for 7 min. For longer night time exposures, I've been using 1:35 for same 7 min. If you are developing by inspection, I first look at it about 5 1/5 min. into the development and then let it go for around 40 sec, and I do this until I see the highlights where I think I need them to be. Hope this helps, David