Marks when Using Jobo Print Drums for B&W negatives. Possible causes and solutions.

[ic-racer]

For the past three years I have compiling data in an attempt to cure issues with marks on the base of B&W negatives processed in Jobo print drums.

Specifically, the ridges of the tank lining can leave permanent marks on the back of the film.

HOW IT HAPPENS:
During fixation, the fixer cannot reach the entire back surface of the negative. If the print is then washed, a permanent mark will form. Re-fixing won't alleviate the problem.


THE SOLUTION:
After fixing in the drum, the negatives need to be removed from the drum and placed in the fixer again so the back of the film can be entirely covered with fixer. This only takes a minute or so and can be done one-at-a time before placing the negatives in a washer.
This has to happen before any HCA, Hypo Clear or water touches the film

Alternative is to do the entire fixation in a tray but that would best be done in the dark.

MY UNINTENDED CONSEQUENCES:

1) Wash water temperature. I used my print washer for the negatives, but it is hooked to cold water. I needed to re-route my 24C water to the print washer.
2) Since the negatives need to be removed from the 2800 drum before any water is placed in drum, the Jobo tank and lift are still laden with fixer. The tank needs to be re-assembled with no film and placed back on the Jobo for the 1 liter rinse.



References:
Film: ILFORD HP5 8x10
Developer: Kodak T-Max
Fixer: Ammonia Thiosulfate
Temp: 24C
Tank: Jobo 2800 series
Processor: CPP2 & Lift

[ic-racer]

Reference Photograph: Jobo 2800 Drum

[Jac@stafford.net]

Is there something JOBO or we can modify to eliminate this issue?
.

[axs810]

Can you post an example photo of the marks you are getting? I just want to see so I know what it looks like

[ic-racer]

Is there something JOBO or we can modify to eliminate this issue?
.

Not sure I understand the question, but Jobo recommends the Expert 3000 drums for film and does not recommend the paper drums for film. Using a paper drum for film is a cost-saving idea because 2800 drums used to be pretty inexpensive. Like ten times less expensive than an Expert 3000 series drum for 8x10 film.

I have an Expert drum for 8x10 film but it is big and heavy for processing less than 5 sheets at a time. Since I had a bunch of 2800 drums I wanted to see if I could get them to work as good as the Expert drum. In terms of processing the emulsion side, they have always been fine as long as the film stays in the slots.

[ic-racer]

These marks show in the print and are permanent as far as I can tell. Re-washing and/or re-fixing won't remove it. The negative is ruined.

[ic-racer]

These marks don't show in the print and seemed to happen almost 100% of the time with the 2800 drum and I lived with them for a number of years. Using the process in the OP even these marks are eliminated.

[ic-racer]

I listed what works in the OP but for the record this is a list of things that DON'T WORK to eliminate the marks:

Cleaning the drum with soap and water
Cleaning the drum with isopropyl alcohol
Cleaning the drum with 409
New old stock 2800 drum still in box, looked like it had never been used
Using Hypo Clearing Agent right after fixing with negatives in the drum
Using water before HCA with negatives still in the drum
Not using HCA, washing in the drum
Not using HCA, washing outside the drum
RE-fixing and re-washing
Dipping in HCA after removing negs from the drum
Pre-wash
Mixing photoflo with the Fixer in the drum

[Kirk Gittings]

As per fixing the negs in the light, BTZS tube practitioners have been doing this for decades. Phil Davis recommended it. BTZS system currently recommends going from developer to stop with the lights on. I dim the lights to just enough to see what I'm doing and rinse the film in the tubes the remove the film to a tray of fixer. Since there is no significant development their is no discernible fog and the fixer removes the undeveloped silver.

No one is suggesting that film won't fog if you just pull it out of the developer and leave in room light without farther processing. It certainly will. However, in BTZS type procedure the cap is removed from the tube after development is complete, in room light or subdued room light as one prefers, and the tube is then immediately placed in a a tray of acid stop bath for 10-15 seconds. After 10-15 seconds in the stop bath the film is removed from the tube, in full room light if you like, and fixed in a tray.

I have developed hundreds of sheets of film this way, and in many cases where I was testing, measured densities with a sensitometer. There is no measurable fogging of the film with this procedure that the sensitometer is able to discern.

Sandy King

[Vaughn]

I had similar problems (see post #6) with even the 3005 drum. Going to a fixer without hardener seemed to be the solution. My best guess was that the hardener hardened the coating on the back of the film before it could be removed by the limited amount of fluid that can reach the back of the film while in the drum.

I do not know for sure it this was the true cure -- but since I have switched to a non-hardening fix, this major problem was not revisited me. Of course, if you do not use a hardening fix, then there goes my theory! Then I would say perhaps the longer pre-development rinse I give the film I give the film (3 to 5 minutes) might have helped solved my problem.