With that film, anything is possible. I was shooting Arista EDU 100 at the box speed and getting terrible results. Found out later that the film is actually Fomapan, and that I needed to shoot it at ISO 50. When I did that it looked much, much better. Tri-X is another film that seems to not be rated correctly by the maker, as pretty much everyone will tell you that it is really a 200-250 ISO film, and my tests say just that. Of course, it being Tri-X, you can shoot it all over the place and get great results.
The maker of the film gives you what they consider to be the correct ISO, but what developer you use, how you meter the shots, how you print the negs, etc will determine YOUR optimal ISO. There really is no other way to do it except to shoot a test roll. What I consider to be the optimal ISO is not what someone else agrees with, nor should it be.
I shot a roll of Tri-X yesterday w/ my FT QL using a yellow filter, and metered it w/ a hand held meter at ISO 125. Then developed it normally. The shots came out perfect. On my NiKon N8008s and using the same yellow filter, I set the camera's TTL meter to ISO 320. These values came about by shooting test rolls and noting the results, and they differ from one camera to another. A dull, cloudy day will also require something different from a bright sunny day. Sometimes I shoot Tri-X at ISO 50 w/ a yellow filter because I personally like that sort of look sometimes. So it just depends on what you want on the finished end. Everything is done to suit my eyes, not anyone else.
Last edited by momus; 04-28-2014 at 10:30 AM. Click to view previous post history.