b/w paper processing in Jobo drums?

[david_haardt2]

Hello folks,

 

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I wondered whether one can process b/w paper in Jobo drums. There is a Jobo drum which can accomodate papers up to 50x60cm (20x24") so that would be rather nice. You only need 300ml of chemicals. But the Jobo web site says that this tank is only for processors, and for colour prints. So my two questions: Can I use it for b/w prints too? (Are there any disadvantages?) Can I use it by rolling it on my desk too, or do I really need a processor? (The Jobo web site says that the smaller drums can be used manually too, but this large one not.)

 

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Best regards,

[pete_caluori]

Greetings,

 

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You can see some similar posts on using FB paper in JOBO drums, by

scrolling down a bit. To answer your question specifically, You can

probably get away with it, but there are some pitfalls to be aware of:

 

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Using the drum off the processor means that the chemistry wont be

distributed evenly at first and may result in streaking. If you use

a long development time this shouldn't be an issue. You probably

wont have complete fixing if you use a short rapid fixer. Rotation

should be bidirectional.

 

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The ribs inside the drum will cause ripples in the paper, which will

come out with sufficient washing and flatening. These ribs may cause

a large sheet of paper to free float inside the drum resulting in a

wasted exposure.

 

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When using a minimal amount of chemistry in a drum that size, the

drum must be perfectly level while it's rotating, or parts of the

print will not be fully developed/fixed.

 

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FB papers get very limp when wet, whereas color or RC papers remain

stiff; this is the reason JOBO doesn't recommend FB prints in these

drums. I have the drum and use it for color & RC prints; I tried it

with FB 8x10's and the paper tends to free floats inside the drum

once it gets wet, but that was with 6 sheets of 8x10. One large

sheet might work, but you'd probably be better off with trays.

 

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Regards,

[david_haardt2]

I am particularly interested in the Jobo drum 3063, because on the

Jobo web site it says that most of the smaller tanks can be used

manually, but this one is for processors only, and I wanted to know

whether this is based upon facts or not. It would also be interesting

how the interior of the drum is made to know which problems could

occur.

 

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Best regards,

[pete_caluori]

Hi David,

 

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This drum is one piece (not including the lid) and as you can

imagine, quite large. The lid contains a small light baffle, but

does not "hold" chemistry. The lids on 2xxx series drums not only

contain a light baffle, but they will hold chemistry. In use,

chemistry is poured into the lid (2xxx series drums.) Only after the

tank is brought to a horizontal position will chemistry contact the

paper. In the lid of the 3xxx series drums, there is no capability

to "hold" chemistry; as soon as it's poured in, it will hit the

baffle and will splash around inside the drum. This is the reason

JOBO does not recommend these drums be used off the processor -

uneven development could occur.

 

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Please beware, I have not tried this, but it does sound reasonable.

If you poured the chemistry in "quickly" and began rotating the

tank "quickly" and developed for a sufficiently long time (I would

think about 3 minutes) then you might be successful with B&W paper,

but don't ever try this with color paper/chemistry. Similarly, you

would have to fix the paper for a sufficiently long time. I would

not try the Ilford 2-bath 60 second fix with this arrangement. You

would also need to insure that the drum rotates on a level plane to

ensure even chemical distribution over the surface of the paper.

When used on a JOBO processor, the drum is spinning while the

chemistry is poured in.

 

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Regards,

[scott_jones4]

Hi David,

 

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Please see at least three previous posts by myself re FB paper for

black and white in the JOBO CPP-2. Single sheets seem to work fine for

me thus far (8x10. I will be testing 11x14 soon and posting the

results. It is best to use the processor I believe after experiencing

all of this. Email if any questions...

 

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Scott

[dick_silven]

David,

I have been using a Jobo #2850 for all my B&W printing for six years

with no trouble. I use Ilford MGIV FB in all sizes from 5x7 to

16x20, processing multiple 5x7, 8x10 and 11x14 prints simultaneously

with repeatable results and no difficulty. The ribs on the inside

are the result of clever design - they are spaced so all popular

sizes of paper fit snugly between a pair of ribs, preventing the

print's floating. I can think of no disadvantages, and the work is

done in the light with very small quantities of chemicals. Can't

comment on hand rolling, but why would there be a problem if you

start with a water rinse as recommended?

Regards,

Dick