Quote Originally Posted by RedSun View Post
Jobo is strongly against using print drums (28xx) for sheet film. There are ridges to anchor the films, but the ridges (rails) inhibit the flow of chemicals to remove the antihalation layer during processing.
I use 28xx drums for 7x17 processing with no issue.

In fact, the idea that the ridges inhibit chemical flow seems farsical to me as the film does not sit hard up against the barrel wall (it only touches in the very middle of the sheet, and only very lightly then), allowing chemicals to get in behind.

In addition, as I always run a double pre-wash (3 minutes/empty/2 minutes), the AH layer is generally gone before the developer touches a sheet. What's left will be removed during the following stages (however, there has NEVER been any AH colour staining of the Developer/Stop/Fixer, leading me to assume that the whole of the AH layer is removed during the prewashes).