Again a newby question but no info was found elsewhere, so I'm hoping you guys can help me out.
I shot a roll of APX 400 rated 200 ISO just for testing. I've found a developing time for 250, but not for 200.
Anyone got a clue ?

I can develope in T-Max(Atomal/dektol)

P.S. It would be nice to know how you can derive the right time for different ISO's based on the time you have gotten good results with, when the film was shot at boxspeed.