The Forma Data sheets seems to suggest that Formapan 100 developed in D 76 stock has a true film speed of 100, Formapan 400 on the other hand seems to top out at 320 with Microphen and just under 300 with D 76 stock. Matches my experience, I shoot 100 at 100 and develop in D76 1:1 with good shadow detail, 400 at 200 developed in Microdal X 1:3 with good shadow details. I shoot Forma 200 at 125 and develop in D76 1:1. Others have posted that the shoot 100 at 50.
Originally Posted by Shootar401