View Full Version : 8x20 JOBO processing

Kimberly Anderson
01-16-2009, 12:25 PM
Hey gang,

I'm going to do my first run of 8x20 today. It's HP5+ and I'm going to run it on the JOBO using the 3063 drum.

I'm wondering if I dare put two 8x20's in this drum which is designed to take 1 16x20. I test-fit a sheet of film in there, and it seems like there's plenty of room...one thing I'm concerned about though, is the film popping out of the groove and ending up sitting flat in the center of the drum.

Any advice/suggestions for processing in this tank? Should I do them one sheet at a time?

I'm going to go with a standard developer and take away 15% of the time to compensate for the rotation development.

Any advice about that?

John Jarosz
01-16-2009, 12:28 PM
What are you printing on?

I've been finding out recently how inherently low contrast FP5+ is.


Kimberly Anderson
01-16-2009, 12:28 PM
I'm going to start with gelatin silver paper...ILford MGIV.

John Jarosz
01-16-2009, 12:57 PM
I've been developing FP5+ in a tray with HC110B. Normal development times give pretty flat negatives. Moderate over development doesn't seem to change this.

That's all I know for now, I have to do more research.


01-16-2009, 01:10 PM
Run your Jobo at the slowest possible setting, below the F(or P, whatever that first letter on the rotation speed dial is), just before it turns off. Then you can use the normal development times for whatever developer you're using. Even if they come out a bit contrasty, you can always print with a Grade 1 or Grade 0 filter using VC paper. HP5+ is not as responsive to expansion/contraction development as other films, even FP4+, so you can overcook it a bit without being too worried about the highlights getting blown out.

Kimberly Anderson
01-16-2009, 01:20 PM
Oooohhh, excellent advice. I'm heading into the darkroom now. I think I'll do an old sheet of 12x20 first to see how it goes.

01-16-2009, 01:38 PM
The man I bought my 7x17 camera from did not use a Jobo. It has been a few years but if I remember correctly he said he got marks bleeding through from the ribs that run around the 3063 cylinder. I have never tried my 7x17 film in a 3063 because of that.

Instead I use 2560 and 2830 tanks connected. Two sheets of film fit into the lengthwise ribs with enough tension to keep them in place. There is only one circular rib in the middle and it does not leave a mark. Perhaps there is another tank combination that would accommodate 8x20 with ribs at 8 inches. The combined tanks are 21 inches deep.

I use Bostick & Sullivan's rollo pyro developer on HP5+, FP4+ and T Max 400. There is a 5 minute prewash then the developer, speed setting "4", 68 degrees F, and dump at 6 minutes. It takes about 20 seconds for the developer to pour out and another 20 seconds for the first water stop to get in, so development is really longer than 6 minutes. I have been adjusting all this for about four years. Good luck. Hope that helps.

John Powers

01-17-2009, 12:31 AM
Too bad the USA Jobo reps didn't continue to build the vacuum-formed inserts.

But there is a way to build a similar insert --
Get some flat carpet runner (not the one with the pegs on the backside to prevent slipping).
Go to a stationary store and get some binder posts -- get the short ones. These were used to bind papers using a 3-hole punch. You may have seen them - a flat screw that goes into another screw-like section, with threads inside the tube.
get some RTV.

Use an electric drill to make holes for the binder posts -- screw them in. Put a little RTV on the backside where the post comes through to hold papers using a 3-hole punch.

Like the Jobo inserts, the pins go along both sides of the long direction of the sheet, and on the ends of the sheet locations, BUT you need to make it longer than the sheet -- slightly, so the carpet runner insert can by wound up into a cylinder and shoved into the 3063.

Now you have something similar to the insert sheets that Jobo created.

Kudos to Rod Klukas for this idea. (I haven't had to resort to this as I have a pair of the jobo 7x17 and pair of the jobo 12x20 inserts, but thought I'd post this here to help others).

....now you can build an insert for the 3063 for 2 8x20 or even 3 7x17.

Kimberly Anderson
01-17-2009, 10:20 AM
Don, sounds very interesting. I would LOOOOVE to see a pic of that. Remember, I'm a photographer (i.e. visual learner). :D

Oren Grad
01-18-2009, 01:16 AM
Michael, I've developed multiple sheets of 7x17 successfully in a 3063 without having them pop out of the ribs. But it may depend on the exact measurements of the film.

The usual caveat applies - my negatives, developed in D-76, are clean, but people who use staining developers have reported unevenness attributed to the ribs.

01-18-2009, 05:20 AM
Michael, I've developed multiple sheets of 7x17 successfully in a 3063 without having them pop out of the ribs. But it may depend on the exact measurements of the film.

The usual caveat applies - my negatives, developed in D-76, are clean, but people who use staining developers have reported unevenness attributed to the ribs.


How many 7x17s have you run at a time in the 3063? I would like to increase from two in my 2500 series to three in a 3063. Did you see any uneven development on either 7 inch side. I had read from Don that the guys who made the inserts, Jobo Ann Arbor, thought there might be too much agitation at the ends of the tank.


John Powers

Oren Grad
01-18-2009, 08:21 PM
How many 7x17s have you run at a time in the 3063?

Three. Before I tried it I cut some paper in that size and practiced loading. And in all honesty, I did mess up once early on and end up with one of the sheets floating around. The key is to figure out in advance the exact arrangement of the film sheets relative to the ribs and how the rib pattern will feel in the dark, leave enough space on your workbench so that you have maneuvering room, and load carefully and deliberately.

I can't say I've seen any problems with evenness in the image. The one problem I did see, with J&C Classic/Fortepan 400, was that the base didn't clear properly and I had to post-treat with a tray of Permawash. OTOH, HP5 Plus has been fine so far.

There's enough voodoo involved that I can never be sure that any other user would get the same results. But my experience has been good enough that I'm comfortable suggesting it as something worth trying, if you're using non-staning developers to make negatives for silver printing.

01-18-2009, 08:58 PM
if you're using non-staning developers to make negatives for silver printing.

Unfortunately I have been using staining developer (rollo pyro) for four years. I'll just have to try an experiment. What $24 worth of film?

Thank you.

John Powers

Kimberly Anderson
01-23-2009, 02:10 PM
I did one negative today with a 2563 and a 2560 tank stacked together. Turned out OK. I am seeing some film fog that I'm trying to identify the source of. I am wondering if anyone has seen any problems stacking those tanks together?

The negative is printable, but it's too bad that there's some fog.

01-23-2009, 02:32 PM

If you think the light is getting in, try reversing the process. In the darkroom dim the lights to adjust your eyes. Put a lighted flash light with a good battery in the tank. Seal the lid. Turn off the lights. Wait five minutes for your eyes to fully adjust and see if any light is leaking out. If you are going to use these combined tanks from now on, seal the light leak permanently, possibly with epoxy with paint or black epoxy. Once you have stopped light leaking out you have probably stopped light leaking in.

If no light shows up, look for other places in the process where it might fog: loading the film holder, film holder fit, dark slide, bellows, unloading. There are a lot of other places where the fog could have happened.

John Powers

Kimberly Anderson
01-23-2009, 10:08 PM
The flashlight idea is good. I'll try that. I did have my MacBook Pro in the darkroom when I loaded...I thought I had it closed and dark when I loaded...maybe I did not. The fog is on the rebates also, so my bet is it happened with the film out of the holder.

01-24-2009, 10:44 AM
The MacBook Pro sounds like a good suspect.

If you try the flashlight and need a black epoxy, most of what i see in the Big Box Hardware stores is clear. We keep a box of grey (almost black) two part Marine Tex on the boat for repairs. "Handles like putty. Hardens Like Steel." Quote from the box. I would imagine the mail order marine supply houses would be a good source. Try to use as little as you can to avoid getting the tank out of balance.

John Powers

Sal Santamaura
01-24-2009, 10:47 AM
...Wait five minutes for your eyes to fully adjust...Complete dark adaptation can take as long as thirty minutes. Waiting only five minutes might lead you to conclude there's no leak when one might exist.

Kimberly Anderson
01-24-2009, 09:18 PM
I usually wait less than five minutes. ;)

Here are some shots of developing...

You can see the fogging in the second shot. :(

01-24-2009, 10:04 PM
Thought I would throw in my 2 cents worth. I have been using a Uniroller reversing base and a Chromega Daylight drum since day one after grabbing Keriks 12x20 several years ago. I have had a Jobo CPP-2 forever and have never used it. I have never had uneven negs and have not been able to figure out a faster method to process negatives. I probably now have 9 or 10 Uniroller bases as I find them on ebay or at photo meets for $30-50. The Omega drums are about the same if in like new shape. The Cibachrome Mark II Processing Drums work great also and they come in various sizes which work for 8x10, 11x14 and 12x20. I have several of the Beseler reversing bases but have found them to rotate too fast and do not rotate past 360 degrees. I may have to use one if the other 9 Unirollers wear out(maybe when I'm 90). The Chromega drum has plenty of vertical ribs top to bottom and hold the 12x20 fine and allow developer to find both sides. So for under $100 you're in business. And like the Jobo the lights are always on as it is a daylight cap with light tight slits so you can enjoy your fine cigar as you prepare to pop the top and pull out your perfectly developed neg...(walls were white, now they're yellow, go figure)....Tav