Jobo Expert drums: do the chems get the back?

[Nicolai Morrisson]

I'm just getting started in 8x10 and don't have darkroom access, so I'm looking at the Jobo Expert drums. Does the chemistry get to the back of the sheet, or is the film pressed tightly enough against the inside of the tubes that none gets there?

I once tried processing 4x5 back-to-back, and while the emulsion side developed without issue, the backs stuck together, didn't let chemistry in, and I had to wash the anti-halation dye out at the end. I'm wondering if I'm going to have the same problem with the Jobo.

Thanks!

[Shailendra]

I just got into 8x10 photography and processed my first few rolls on a Jobo 3005 tank. I had consistent processing but used about 10% more fluid than suggested. I think you should have no problems with the Jobo Expert Drums.

[Ron Marshall]

It does get to the back. The Jobo is a good design and can easily and consistently be hand-rolled.

[SamReeves]

Agreed. Really excellent, but I add 20% more just to be on the safe side. Should a catastrophic life problem happen.

[Oren Grad]

The chemistry does get to the back. I was told once by a Jobo rep that the wells aren't simple cylinders, but have a subtle barrel shape that facilitates circulation. I've never tried verifying that, but I've used Expert drums for many processing runs on a CPA-2 over 10 years, and the film bases have cleared perfectly every time.

[Deane Johnson]

Why does the chemistry need to get to the back?

[Jan Pedersen]

The fixer need to get to the back to clear the negative and that is a constant problem for me. I have used 50% more chemistry than called fore but still need to clear the film in a tray. Not that exited about the Expert drum (3005).

[tim atherton]

The fixer need to get to the back to clear the negative and that is a constant problem for me. I have used 50% more chemistry than called fore but still need to clear the film in a tray. Not that exited about the Expert drum (3005).

8x10 or 5x7 in the Expert Drum?

I've never had to re-fix any of the hundreds of sheets of film I've processed beyond what happens in the drum.

I'm trying to imagine what you must be doing wrong?

[Deane Johnson]

The reason I asked is that I used to use some Calumet plastic sheet film holders that held the film firmly against the plastic. Their indication was that there is no need for the back to receive chemicals as all of the action is in the emulsion. The back is nothing but the estar or whatever the base is made of.

It puzzles me that you need fixer to the back to clear the film. I'm not saying you're wrong, it's just something I never realized.

[Jan Pedersen]

Tim, it is the same problem wheter i dev 5x7 or 8x10
I presoak for 5 minutes but still have antihaltion dyes in spots and ocationally spots not completely fixed to.