I have a large amount of this film and would like to keep as much speed as possible without the grain going too much out of control. quote]
I love using Microphen, but I push HP5 to 650 ASA (a little more than half a stop), but I use 3:1 dilution. The developement times are long and extended but are worth it. (23 minutes at 20 degrees C) The slow developement keeps the grain small.
I don't follow Ilford's recomended aggitation. I only invert the tank for ten seconds the first minute, and for each additional minute I twist and rotate the tank for ten seconds. I beleive this leads to slight underaggitation that also slightly lowers contrast. Probably also helps me keep shadow detail also.
My negs can be straight printed on number 2 graded paper. Grain remains small.
Calzone