Paterson orbital processor for 4x5 negatives and washing

[Mark Pope]

I've manged to acquire a couple of Paterson orbital processors, which I intend to use for processing 4x5 sheet film. I got the idea from Roger Hicks and Frances Shultz's excellent book on LF and MF photography.
One question that I have concerns film washing.

When I wash roll film I follow Ilford's recommendations for film washing (fill tank with water at same temperature as chemicals, invert 5 times, empty, refill, invert 10 times, empty, refill, invert 20 times and then for good measure empty, refill, invert 40 times and then a final rinse with a couple of drops of Ilfotol.

Will using a similar process with the orbital processor result in a sufficiently well-washed negative, as the volume of water used will be quite a bit lower than used for a developing tank?

 

[Dave Miller]

The use of these gadgets for developing sheet film has been discussed several times on this forum, and it may be worth a search to read them. I too followed Roger’s advice, but have modified mine differently. As for your question the wash method you describe will I’m sure suffice even with the reduced water quantity involved.

I fill and empty the tray with water about 10 times, placing it on the rotator for about 15 seconds for each fill. You must be confident that the water can get under the negative so as to clear fixer from both sides of the negative, even though it is only wanted on the upper emulsion side for processing.

 

[Mark Pope]

Thanks Dave what did you do to yours? I've not modified the processors (yet). IIRC Roger mentions using a dremel tool to roughen the bottom of the processor. Not quite sure what level of 'roughness'; is needed or whether it's necessary to cut little grooves in it (maybe a little job for tomorrow as I have the day off and the weather forecast isn't exactly great)
BTW, I haven't got a motorised base - not sure what (if any) difference this would make though.

Cheers

 

[Dave Miller]

Mark,
The motor base is essential in my view, as rocking and rotating the tray on the hand-base is tedious, as you will find out.

I use slow setting epoxy adhesive to make lots of small blobs (20 or so) over the bottom of the tray. These settle, as the glue cures, into smooth domes that lift the film just enough to break the suction effect that you get with an untreated base. This makes the film easier to remove. I have trays that I treated four or five years ago in this way still in use although the epoxy has discoloured a little.

Roger’s idea of roughening the base with a rotary file will work just as well.

I also use these trays for processing my small prints, and I find the “blobs” also help when removing the prints after their initial washing.

It’s a great pity that these trays were never produced for 16x12 paper.

 

[Roger Hicks]

DON'T use a motorized base. In areas of even tone you can (with the wrong amount of developer) get uneven development, at least with 8x10 (I've not had it happen with 4x5). I only discovered this after recommending the use of these things -- sorry! Manual agitation, as random as possible, has thrown up no problems yet that I have encountered.

I just 'kissed' the base of mine with a Dremell to roughen it all over. All you're doing is stopping the film sticking to the base so that the backing clears. This also helps washing.

With washing, I use 5 changes of as much water as you can conveniently get into the thing: 15 sec, then 30 sec, 60 sec, 2x 2 min, followed by distilled water and a tiny bit of wetting agent. I've not tested this for residual hypo because I'm reasonably confident on theoretical grounds that it is more than equivalent to the Ilford's wash cycle.

(Addendum: Dave beat me to the reply and if he's had no trouble with 4x5 maybe it's only with 8x10).

Cheers,

Roger (www.rogerandfrances.com)

 

[pauldc]

I use a tube of silicon sealant (I got it from a aquarium shop for sealing fish tanks but I think it is the same stuff you can use as a sealant in the bathroom) to make the blobs on the bottom of the orbital. It is very soft and rubbery and does not scratch. Works very well.

 

[Dave Miller]

I use a tube of silicon sealant (I got it from a aquarium shop for sealing fish tanks but I think it is the same stuff you can use as a sealant in the bathroom) to make the blobs on the bottom of the orbital. It is very soft and rubbery and does not scratch. Works very well.

The difference is that the household stuff has an anti-fungal additive which the aquarium stuff doesn’t since it kills fish as well as fungus. I only know this from the time I sealed a fish tank with the household variety.

 

[Mark Pope]

Thanks everyone for your adviuce. As it happens I have some Wickes bathroom and kitchen sealant in the garage. I think I'll get and try that first. It's got plenty of time to cure as the camera won't arrive until Tuesday at the earliest :-(

BTW I was lucky enough to acquire two orbital processors for under £10 from a local dealer. They seem to go for silly money on Ebay - I saw one go for £100!

 

[Steve Smith]

I scored the base of mine with a scalpel blade. It works fine but I wish I had heard about the epoxy dot method before I did it as this sounds like a better idea.

I do not have the motor base and do not find rotating by hand tedious. I just turn it (it doesn't actually turn, just rocks in a circular motion) about one cycle per second for the same time as stated for normal agitation.

I try to stop it with a different corner in the down position each time but if you do some trials with the lid off, some scrap film and some water instead of developer, you will see that it works really well and you don't have to worry about the high point being out of the developer. I had to do this to convince myself that the recommended amount of developer was enough - it was!

 

[Mark Pope]

I've just had a go with the silicon sealant - I don't have any epoxy in the garage at the moment and can't be bothered to endure going to my local DIY store - I'd rather be in the darkroom. So, what I've done is to put 4 parallel tracks of the stuff for each sheet of film. It took all of 10 minutes and most of that was getting into the sealant tube. Hopefully, this will do the trick...we'll see. If it doesn't work, it shouldn't be too onerous to remove it and try something else.

Cheers