After years of tray developing I have to switch to a lab for film development. I shoot Bergger BPF in the 8 x 10 size and rate it about 100 asa, maybe a bit lower (I prefer slightly dense negatives with good shadow detail.) The lab hasn't worked with Bergger sheet films before. They use a large tank machine processor (dip and dunk) with "seasoned" XTOL. I don't know their dilution or if XTOL is a standard dilution for a machine like this. Does anyone have an educated guess as a start time for a Normal negative? What about expansion and contraction development? +/- 20 to 30% ? I have some negatives to test, but I need a good place to start.

Thanks for your help.