The noted volume on a Jobo 1500/2500-series tank is the least amount required, you can run higher volumes. E.g. for watering a single film after development in a 1510 (noted volume 130 ml) I use 200 ml, and have the impression I get 200 ml back using the lift. So a 1520 should be fine for 2 films by increasing the volume from 260 to 400 ml.(posted 8516 days ago)And this math might solve my Xtol problems: Using a std. test roll with 10 steps plus some pictures everything was fine with 65 ml stock plus 65 water, because it was 65 ml for half a roll. The actual run of two TMY films with 130 ml stock and 130 ml water gave very thin negatives. I might go to either 100 ml stock for 1:1 or straight Xtol (130 ml).
Regards,
Wolfram