I have a couple ATP 1.1 starter kits (roll of 35mm film, 20mL Rollei ATP DC developer, and fixer). The instructions say to mix 20mL developer with 230mL water (250mL total) for a 1+11.5 dilution. My Patterson tank suggests using 290mL, so to avoid potentially ruining the top/bottom of every frame on the roll I diluted to 1+13.5 and followed the rest of the directions accordingly, but I did not adjust the development time. In general the negatives look very good overall. However, they seem to be far more underdeveloped than expected. I bracketed a lot, and it looks like the best frames were at roughly EI 12. According to the info packet the ATP DC developer should yield EI 32-40. Is that much of a shift expected when effectively the only difference is a ~7% dilution vs the recommended 8% dilution? Can I get away with using only 250mL in the Patterson tank in order to use the suggested 1+11.5 dilution, or should I repeat with 1+13.5 and extend development time a little...7 minutes instead of 6? Maybe 8 minutes? The second roll I shot was also bracketed but this time more in the range of ~8-32 rather than ~12-40. Assuming I do everything exactly the same this roll should turn out fine, but I'm still curious about this because I'd love to use this film more in the future.