Streaks with JOBO Processing

jkorpi · Jan 8, 2016

I am over in Italy working on a project, and I brought my JOBO CPE 2 processor with me. For the most part I do not have problems with the processor, but I continue to have occasional issues with streaks in occasional images. This only happens ever once in a while, but I want to figure out the issue before this happens again. Attached is an example of an image where this happens. Look at the sky in the left of the scene.
I have had some people say it is the fixing of the image. This makes sense except for the fact that I fix the image for the proper time, with proper temperatures and with new fixer.
Please help if you can.

RobC · Jan 8, 2016

I suspect its tank filling speed with dev running over film. Fill tank and get it rotating as fast as possible.

It could also be some condensation or heat marks on film in camera as those marks could be where film has been touching when spooled in camera.
Possibly film pulled too tight on spool when there was some condensation or film was warm/hot in camera.

Difficult to be sure either way.

Xmas · Jan 8, 2016

Refix immediately.
In future use an acid stop and fix by inspection...

RobC · Jan 8, 2016

Xmas said:
Refix immediately.
In future use an acid stop and fix by inspection...

Ahem, that is a colour image. Portra which means colour negative. Methinks you never use acid stop with colour film, its kills/fades the dyes. Certainly fix should be neutral to alkaline.

macfred · Jan 8, 2016

From an old discussion on photo.net Streaking skies, 8x10 Jobo C-41 developing http://photo.net/large-format-photography-forum/00bbsF including a link back to an APUG discuss.

wildbill · Jan 8, 2016

RobC said:
I suspect its tank filling speed with dev running over film. Fill tank and get it rotating as fast as possible.

It could also be some condensation or heat marks on film in camera as those marks could be where film has been touching when spooled in camera.
Possibly film pulled too tight on spool when there was some condensation or film was warm/hot in camera.

Difficult to be sure either way.

I commented on your LF forum post as well.
The machine is on and drum rotating while filling it, yes?
If not, there's your sign.
FWIW, I've processed c41&e6 w/o a pre-wash and never had this issue.
Are you following jobo's instructions word for word?

Sirius Glass · Jan 8, 2016

The machine must be turning when chemicals are being poured in.
Using stop bath after the color developer eliminates a number of possible problems.

mnemosyne · Jan 8, 2016

RobC said:
Ahem, that is a colour image. Portra which means colour negative. Methinks you never use acid stop with colour film, its kills/fades the dyes. Certainly fix should be neutral to alkaline.

It is only citric acid that shouldn't be used with color materials (possible negative effect on dye stability as you mentioned), but acetic acid is safe and recommended depending on the workflow.

pentaxuser · Jan 8, 2016

The standard CPE-2 hasn't got a lift, has it? Mine hasn't so the tank has to be filled then placed on the magnetic drive. I have never experienced these problems. I don't see how you pour in chemicals with the machine turning. If the machine turning was essential while pouring in the chemicals then every standard CPE user would experience problems surely. There has to be more to the problem doesn't there?

pentaxuser

RobC · Jan 9, 2016

well if you take too much time over filling and putting the tank in the machine then exactly what is being seen could easily happen.

pentaxuser · Jan 9, 2016

RobC said:
well if you take too much time over filling and putting the tank in the machine then exactly what is being seen could easily happen.

Yes I take your point RobC. There is no case for delay, I agree. I was just pointing out that while posters seemed to be settling on the need to fill the tank while it was rotating as the solution to the OP's problem this is impossible on the standard CPE2 which maybe some posters had overlooked.

My own experience, to give the OP some hope, is that if the tank is filled then fitted to the magnet immediately and switched on instantly then I had never had the problem of streaking

pentaxuser

Photo Engineer · Jan 9, 2016

Using a prewet and an acid stop should help. However, the green bleach III is more acid than the red bleach and should do the job without a stop. Using acid fix or acid solutions after the fix can affect the dyes.

PE

Doc W · Jan 9, 2016

When I used to hand-roll a Jobo Expert Drum, I would sometimes get streaks. I attributed this to the fill/empty steps. This is why the lift is so advantageous.

Sirius Glass · Jan 9, 2016

Sirius Glass said:
The machine must be turning when chemicals are being poured in.
Using stop bath after the color developer eliminates a number of possible problems.

pentaxuser said:
Yes I take your point RobC. There is no case for delay, I agree. I was just pointing out that while posters seemed to be settling on the need to fill the tank while it was rotating as the solution to the OP's problem this is impossible on the standard CPE2 which maybe some posters had overlooked.

My own experience, to give the OP some hope, is that if the tank is filled then fitted to the magnet immediately and switched on instantly then I had never had the problem of streaking

pentaxuser

If you have the lift you can fill the tank while it is turning. When you lift the tank it stops turning until you set it down, then it will start turning again.

RobC · Jan 9, 2016

Sirius Glass said:
If you have the lift you can fill the tank while it is turning. When you lift the tank it stops turning until you set it down, then it will start turning again.

As has been mentioned already, I don't think the CPE has the lift option and it certainly didn't come with one. So you fill the tank and then put it on the drive which should be done with all haste.

Sirius Glass · Jan 9, 2016

The lift is an accessory which can be added to or comes with the CPA(+) and CPP(+) and I believe the CPE.

wildbill · Jan 10, 2016

The cpe2 has a lift option. There are pics titled "cpe with lift" as well but I've never seen one in person and the literature doesn't specifiy cpe, only cpe-2.
https://images.search.yahoo.com/yhs...-001&fr2=piv-web&hspart=mozilla&hsimp=yhs-001

Doc W · Jan 11, 2016

My CPE-2 has a lift.

Sirius Glass · Jan 11, 2016

(there was a url link here which no longer exists) , Welcome to APUG

Streaks with JOBO Processing

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