Alan, I'm using a different baffle now, but the same concern is true of it: Flow will be different compared to a roll. The odd thing is: With XTOL, the graphs for strip and roll match. But with my dev, a strip needs more time.
Three rolls have confirmed this. I wondered if I'd made a mistake with the first roll, so I ran a second -- with identical results. Last night, I ran a third roll with a shorter dev-time, and it matched XTOL's graph well. Here's a summary of what I've run (with and without adding propylene glycol):
Originally Posted by Gerald C Koch
XTOL strips and roll -- gave nearly identical graphs.
Strips with no added PG: 12.25 min is correct (where "correct" means "matches XTOL's graph").
Strips with added PG: 13.1 min is correct.
Rolls with added PG: 12.25 min is correct.
It's acting as if having a low fluid-to-film ratio quickly neutralizes the retarding effect of the PG, causing development to proceed at its normal (higher) rate.