Help with negative problem

[Robert Oliver]

Curious if anybody could help figure out this problem with inconsistent developement of negatives.

TriX 320, d76 1:1, Jobo 4x5 6 sheet holder in tank processed in a unicolor drum for 11 minutes. (12.75min recommended with normal small tank agitation and I subtracted 2 minutes or approx 15% for rotary tube processing)

The streaks follow the direction of the rotation.

The picture in the link has had extreme level adjustment to make neg problems stand out better. In the real scan, the streaks are faint but very noticeable.

[Mark Sawyer]

I'm not a rotary processing kinda guy, so take this with a grain of salt...

It's obviously an over-developed streak down the middle, which almost-as-obviously must be from be from some sort of turbulence/agitation/drainage issue in the developing solution down the middle of the negative during rotation, (ie: it's getting more agitation there, so it's developing more).

I'm not sure of a solution, other than maybe try more solution, (increase the volume ome developer in the tube). That might change the fluid dynamics inside, and keep the film in the developer longer during each rotation. Changing the rotation speed might affect it too.

[Henry Ambrose]

What was the total amount of developer in the tank? And which tank?

[Robert Oliver]

28 ounces of solution (1:1) in the tank that has room for only one 4x5 (6 sheet capacity) holder. Jobo multitank2 # 2521. There were 5 sheets in the holder.

[photographs42]

More information would help.
1. Has this happened before?
2. Were all 5 negs similarly affected?
3. Were these the first negs developed in the session? If not, could there have been residual fixer in the tube from the previous processing?
4. Did you use a prewash?
5. Was the developer freshly mixed or was it reused?
6. Does the tank rotate in one direction only or does it reverse after a few rotations?
7. I'm not familiar with the 2521 tank. Does it have a film holder insert?
Jerome

[Robert Oliver]

1. yes
2. no. The second shot from the same scene was fine.
3. First and only negs of the session
4. no prewash
5. stock solution was 1 week old stored in collapsable bottle. First time use.
6. one direction rotation. Forgot to reverse it.
7. it has a 6 sheet film holder inside a short and stubby jobo tube.

[photographs42]

OK, more questions.
1. Since it has happened before, does it happen often? Always?
2. Is it always in the direction of rotation?
3. Have you given any thought to this being a camera/film holder light leak?
4. If it doesn’t affect every neg, does it affect only consecutive negs on the reel or does it skip some?
5. Do the streaks correspond in any way to some sort of obstruction on the reel structure?
6. If you compare the affected negs, is there a pattern or are the streaks totally random?
7. How much film have you, or do you process? Have you processed a lot of film this way w/o problems and this just started or have you been plagued by this from the start with this equipment?
Jerome

[bob carnie]

Robert

This is a typical road rut problem that we encountered with rotary , specifically with 120 film in PMK with more than one film loaded. some would have this problem and others would not.

To solve this problem you must hand agitate or inverse the tank within the first twenty seconds of development. Your problems should go away, We had exactly the same two minus density flow marks running in the direction of the rotation . We tried every concievable correction . Basically the quick inversion is what solved the problem.

Start the motar, let run for two or three turns, take off the tube, completely inverse as you would hand develop and put back on the machine for the balance of the run.

[Henry Ambrose]

"Jobo 4x5 6 sheet holder in tank processed in a unicolor drum"

How do you use the Jobo tank inside a Unicolor drum?
Thats a new one on me - but it seems possible? Is that what you did or is it a typo?

I've used the longer Jobo tanks on a Unicolor base but the short one reel version won't work that way.

It seems you are using enough fluid.

About the only thing that comes to mind here is you might try a pre-soak. Fill the drum with water, roll it a few revolutions and let it stand for a couple of minutes. Then pour out the water, pour in the developer and put it on the roller.

[Kirk Keyes]

6. one direction rotation. Forgot to reverse it.

Look no further than this answer. You must reverse the rotation of the tank occasionally otherwise the bromide streaking shows up from the lack of turbulance in the flow of the developer.