Jobo CPA for b/w processing?

nostalgix · Sep 19, 2008

Hello,

I could get an old Jobo CPA for small money. I am wondering now if it will be possible to use it for processing my b/w films?

Thank you in advance.

snallan · Sep 19, 2008

I use my CPA for B&W as well as colour. Some recommend cutting your development times by up to 15%, but I have found that using the times I had established for hand agitation work for me on the Jobo.

Using a Jobo processor is particularly handy if you process a lot of film, and if you have somewhere where it can be set up (semi-) permanently.

nostalgix · Sep 19, 2008

Thank you, Steve,

snallan said:
Using a Jobo processor is particularly handy if you process a lot of film, and if you have somewhere where it can be set up (semi-) permanently.

I think that won't be the case. I still will have to use the bathroom.
The reason why I am thinking about it is because I then would be able to keep all chemicals in there and all is temperatured at 20°C.

Maybe you can tell me a few more details? How do you use the stop bath, fixer and watering in the CPA? Or do you do some steps the traditional way?

bdial · Sep 19, 2008

There is really no difference, except that the Jobo takes care of the agitation, and it has an automated tempering bath.
At the end of each step you dump the contents of the tank, and pour in the next chemical. For stop and fix, I use the same times I would with manual processing. For washing, it is easier in a film washer or placing the open tank under a faucet, or use the Ilford wash method.

I'm not sure it would be practical to leave the unit on all the time, I think the unit only operates the heater when the recirculating pump is on.
Judging from the internals of my CPP it is not robust enough for continuous operation. However, you can certainly start it up a short time before you want to start and it should have everything at the right temperature pretty quickly.

Barry

nostalgix · Sep 19, 2008

Thank you, Barry. I think you are right, washing might be easier outside of the CPA.
I think I will give it a try then.

jeroldharter · Sep 19, 2008

You want a unit with a "Lift" which is a light tight mechanism that allows you to dump the chemicals for one step and then pour in the chemicals for the following step. Once you have one, you can't imagine going back to manually removing the tank, dumping, filling, and re-attaching the tank.

You should not use Photo-Flo or similar srufactants with the plastic reels or they can gum up. I remove the film from the reel, hold its ends between outstrectch hands in a large arc, and then pass the arc through an 8.10 inch tray of Phot Flo and that works fine.

There is no need to leave the unit on all of the time. If you leave the tank full of water, nasty stuff starts growing in there. You should empty it after each use or after a few days of use and refill with water. It heats quickly so I just tun mine on about 1 hour + before I need it and the chemicals are tempered. You should not move the unit when full of water because it is brittle plastic and might break. It has a drain valve along the bottom edge (to which you could attach a hose) so make sure you place it somewhere that draining is possible.

Mark_S · Sep 19, 2008

I use a CPP, which is very similar to the CPA for film processing - both color and B&W. Since it is light tight, you only really need a darkroom to load the drums with the film, and you could then locate the CPA somewhere other than in the bathroom - basement?, laundry room? etc, so you may be able to set up the processor either permanently or semi-permanently.

In my flow for B&W I use the CPP for a pre-wash, develop, stop, fix, prelim rinse and then remove the film from the CPP and do a final rinse elsewhere.

Things that I like about the CPP:
Allows me to process a lot of film at a time.
I get very consistent results.
Makes it easy to keep the chems at the proper temp.
sealed system means that I don't have as much contact with the chemicals as I do with other forms of processing.
Requires very little chemistry - environmentally friendly.

Things that I don't like:
Not well supported by the manufacturer (spare parts, etc)
Not as sturdy and well built as I would like - much of the machine is made of relatively thin plastic, the arm on the lift does not seem like it is happy to lift a large processing drum with 1L of chemistry in it, etc.

snallan · Sep 19, 2008

I am lucky in that I have the set up ready to go at any time. I've never had problems with thigs growing in the bath, but mine is in a darkroom. Though I have considered occassionaly adding some sterilising fluid for babies bottles, just to take care of anything that might try and grow.

I carry out all of my washing in the drum, on the processor. I give three, one minute washes, followed by two, two minute washes. Like Jerold, I treat the negs with rinse-aid off of the reels. Most of my negatives get selenium toned, but I do that later, off of the processor.

As for support or maintenance Arvid, you may find it much easier as you are based in Germany. Arigram has a thread about a Jobo problem, and someone gave the name of a guy in Germany who services the Jobo processors.

nostalgix · Sep 19, 2008

Thank you all a lot for these details.
Sounds like a comfortable way to process in the future. I am really looking forward to it.

Bruce Osgood · Sep 19, 2008

One thing I would add.... I use the CPE2+ for 35 MM and 4X5 negatives. It is a God send. BUT, the problem I have is the water that comes from the tap is hardly ever below 72-F and usually about 74-F. This presents a problem in bringing the temperature down, not up. Perhaps the CPA or other models can chill the water as well as heat it. I've added a step where I buy a bag of ice and put it in a 3 gallon bucket and fill it or add a tray of ice from the refrigerator to the tank. When the water in the bucket temperature drops below 68-F I add it to the Jobo tank and let it warm to the desired temperature.

nostalgix · Sep 19, 2008

Bruce Osgood said:
One thing I would add.... I use the CPE2+ for 35 MM and 4X5 negatives. It is a God send. BUT, the problem I have is the water that comes from the tap is hardly ever below 72-F and usually about 74-F. This presents a problem in bringing the temperature down, not up. Perhaps the CPA or other models can chill the water as well as heat it

I think there will be no difference between the CPE2 and the CPA. But that won't be a problem here, because I can get the water almost frosty from the tap. The problem is that it sometimes may take forever to get warmer water. And to hold the temerature at a level is difficult sometimes of course.

Iwagoshi · Sep 19, 2008

jeroldharter said:
You should not use Photo-Flo or similar srufactants with the plastic reels or they can gum up. I remove the film from the reel...

Jerold,
No Photo-flo in the plastic reels, thanks for the tip!

During the Summer, to keep the temps down to 20C, I use ice cubes or put a frozen 0.5 liter bottle of water in the last square hole.

Lack of support: I'm looking for a second just for the parts, especially circuit boards.

Terry

CCOS · Sep 19, 2008

Short answer yes...
The longer one, yes it god for that just take som 10-15% of the time if there are no rotations times available.
The other reason is that you use only the half chemistry at rotaion ..
so go for it and good luck

Jesper

ic-racer · Sep 19, 2008

madhatter said:
Maybe you can tell me a few more details? How do you use the stop bath, fixer and watering in the CPA? Or do you do some steps the traditional way?

I have my six bottles set up as follows:

1) Developer
2) Stop Bath
3) Fixer
4) Water Rinse
5) Permawash
6) Rinse (to clean the lift and flush the system)

Its a great system. I do 8x10, 4x5, 120, 35mm, 16mm and Minox with the Jobo processor.

nostalgix · Sep 21, 2008

Just payed for the CPA. I hope it will arrive within the next week, so I can use it next weekend already!

Jobo CPA for b/w processing?

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