Uneven Development w/ Jobo CPE-3 + Lift

MattKing said:

At the risk of being difficult....
When I look at the photo of your nearly blank negatives, I see un-evenness that, at least in par could only reasonably result from un-evenness of exposure.
This is the photo I mean:
View attachment 278745

Note that the vertical areas of reduced density are adjacent to the space between the frames, and only there - not repeated anywhere in the middle of the frames.
I don't believe that is un-evenness which is development related, because I don't believe that there is any way that flow of developer could be affected by the location of the space between the frame.
I agree that the artifacts along the top could be due to development issues, but I find the narrow line along the top edge of the rebate to be interesting. That looks to me to be either an un-fixed area, or an area that has been light struck.

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@MattKing The vertical areas on the left/right edges with reduced density was most likely vignetting caused by shooting my 28mm Elmarit-M at f2.8. Won't debate that! I also don't have any of my other test rolls from different cameras/lenses available anymore to confirm. But the top artifacts are absolutely development related and only happen in the Jobo. The narrow line is from the film sitting tightly on the reel and happens frequently when using stainless steel reels in my experience, Jobo or not. I did try using plastic reels as well and the uneven development still occurred.

@Adrian Bacon I believe the CPE-3 runs at 70rpm. It rotates in both directions and there is unfortunately no setting to change that. The CPE-3 is very simple, has an on/off dial, a temp dial, and a rotation on/off dial, and that's it

Maybe next time I have my Jobo set up and I feel like wasting time and film we can run the gamut and I'll livestream me shooting test rolls on different cameras and processing it every which way possible (described in my original post) to try and find out why I've been cursed with uneven development with black and white film on my Jobo. But that probably won't happen, I don't see myself using the Jobo for black and white and that's fine. Maybe there was truth to the Darkroom Cookbook not recommending Jobo for black and white?

Adrian Bacon said:

what speed is it rotating? In my experience, faster is better and larger solution volumes.

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I disagree, the rotation speed should be based on the film size. I use 'P' for 135 and 120 and '4' for 4"x5" per Jobo instructions.

Sorry, I haven't read all of the above posts.

But, have you tried the 5 minute presoak that JOBO recommends for every film/developer combination?

Adrian Bacon said:

I primarily use a jobo Duolab, though I have other jobo machines, none with lifts, and I only use 1500 series tanks for film. Contrary to what other people may think, I don’t like the whole reversion thing that other jobos do, and I think it’s a source of many problems. If your tank is perfectly level and has max fluid capacity (something else I always do), there shouldn’t be any surge marks as the film is simply being rotated through the chemistry. I also never prewet.

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I agree with you on the little Duolab. Per Jobo, maximum film processing is with a 1520 tank, period. You can develop 2 135 films on 2 1500 series reels or 2 120 films loaded on to one reel.

The Duo part, is the four slot tanks that hold an 8x10 film hanger. I've never used the slots. I've never seen any development problems with any Jobo processor*. You need to follow the instructions with leveling, as Sirius notes rotation speed, use adequate solution, don't overload the tanks or processor.

*It's easy to get streaks on paper or large sheet film with 1 way rotation. Bromide drag.

I would definitely try to get a CPP3 or good used CPP2 with a lift for heavy work

Inversion agitation is the way to get rid of this uneven density.

You should be careful how much inversion you use. I tried developing 4x5 in a jobo with their six sheet reel using just inversion in a full tank and got some serious flow marks. I then tried it with rotation and the proper amount of fluid and got even results. My guess is the inversion is moving the fluid at 90 degrees to rotation direction causing the flow marks.

glbeas said:

My guess is the inversion is moving the fluid at 90 degrees to rotation direction causing the flow marks.

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You sure can have problems with inversion as well. But I thought he was rotating 35mm film? The plus density in even skies look typical to continuous rotation.

FotoD said:

You sure can have problems with inversion as well. But I thought he was rotating 35mm film? The plus density in even skies look typical to continuous rotation.

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All depends on the geometry of the reels. The 4x5 reels had quite a bit of stagger to the film position and the ends hanging out got the worst of it. 35mm reels are built different but the fluid flow will still be different inverting versus rotation. The trick will be determining how much of each direction will be enough to randomize the flow.

If you use the 2509n reels you need to use the end plates. For 4x5 I actually prefer these reels to the Expert drums. I've never had a problem.

FotoD said:

Inversion agitation is the way to get rid of this uneven density.

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The old rotate while inverting is pretty much perfect for roll film. I developed a lot of film in Paterson tanks over the decades. I always thought Jobo was screwy, I wouldn't even consider. Then I got one and love it.

FotoD said:

Inversion agitation is the way to get rid of this uneven density.

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glbeas said:

You should be careful how much inversion you use. I tried developing 4x5 in a jobo with their six sheet reel using just inversion in a full tank and got some serious flow marks. I then tried it with rotation and the proper amount of fluid and got even results. My guess is the inversion is moving the fluid at 90 degrees to rotation direction causing the flow marks.

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FotoD said:

You sure can have problems with inversion as well. But I thought he was rotating 35mm film? The plus density in even skies look typical to continuous rotation.

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The Jobo tanks were designed for rotation on the Jobo machines. Inversion of Jobo tanks is outside the design envelop of said tanks.

mshchem said:

I agree with you on the little Duolab. Per Jobo, maximum film processing is with a 1520 tank, period. You can develop 2 135 films on 2 1500 series reels or 2 120 films loaded on to one reel.

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Actually, you can put the rollers on the far left roller slots and use a 1520 stacked with a 1530 or 1525 extension tube. This uses 600ml of solution, and lets you do up to 5 135 rolls, or 6 120 rolls if you stack 2 rolls per reel. Of course, depending on what developer you're using, this usually is too many rolls for the solution capacity. I generally limit it to 3 rolls of 120 (one per reel), and either 3 or 4 rolls of 135 depending on if their 36 or 24 exposure rolls. Doing that gets good results.

I generally put in about half a liter of chemicals in my Jobo processor regardless of the number of rolls of film. Then each chemical goes back into the bottle with replenisher for the developer as needed.

Adrian Bacon said:

Actually, you can put the rollers on the far left roller slots and use a 1520 stacked with a 1530 or 1525 extension tube. This uses 600ml of solution, and lets you do up to 5 135 rolls, or 6 120 rolls if you stack 2 rolls per reel. Of course, depending on what developer you're using, this usually is too many rolls for the solution capacity. I generally limit it to 3 rolls of 120 (one per reel), and either 3 or 4 rolls of 135 depending on if their 36 or 24 exposure rolls. Doing that gets good results.

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I made a larger diameter roller to allow the use of a longer stack of 1500 series modules. Without the, I believe, 1 inch diameter rubber wheel, in my case, the 1500 series tanks, like 1526 etc would, not engage properly with the drive gear of the Duolab. I had to try it, but the little Duolab motor was struggling to keep up. Used as designed, as a little, big, amateur processor they work great. Also for consideration, the tank cogs are different than the ordinary cogs, and impossible to find at a reasonable price. I tend to be an accumulator, I have 3 of the little buggers, HILARIOUS!

Sirius Glass said:

I generally put in about half a liter of chemicals in my Jobo processor regardless of the number of rolls of film. Then each chemical goes back into the bottle with replenisher for the developer as needed.

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Good advice.

Sirius Glass said:

The Jobo tanks were designed for rotation on the Jobo machines. Inversion of Jobo tanks is outside the design envelop of said tanks.

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No, at the time of their first processors Jobo tanks to be used in rotation partially got an inversion action, to avoid perpendicular flow pattern.