Tank Processing

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I have an opportunity to buy three Kodak hard plastic non-daylight processing tanks, seven 5x7 hangers, one 4x5 hanger, and four 8x10 hangers -- all used and in good condition -- for $75. I am wondering what type of deal this is and the pros and cons of tank processing over tray processing. I do tend to scratch negatives with tray processing more than four 4x5 or two 5x7 negatives at a time. Thanks for the input Jim Worthington

-- Jim Worthington (jcw@phr.ccmail.compuserve.com), September 02, 1998


Tank processing is OK. And the deal sounds fine. The main problem with tank processing is the fact that you need a large volume of chemistry to fill the tank. (An 8x10 tank takes 3.5 gallons of solution!) Not good if you use one-shot developers as I do. You'll have to replentish, extend your developing time, or dump your developer after each session. Tray processing is best, I feel, at least for b&w, where temp control is not a problem. I harden my negs before washing, so stratches are kept to a minimum. Use a 5x7 tray for 4x5 or 5x7, an 8x10 for 8x10. This way the film has less opportunity to scratch. Practice makes perfect. T-Max films scratch easily, regular films less easily. A tray with holes drilled on one end is fine for washing. If you do go with tanks, beware of excessive agitation, which will cause streaks as developer rushes through the little holes in the hangers. And loading hangers takes some getting used to! Also, the edges of the holders are extremely sharp, so handle them carefully so as to avoid scratching in the tank. Finally, you will have to remove the film from the hangers for drying. Good luck. http://www.ravenvison.com/rvapeter.htm

-- Peter Hughes (leonine@redshift.com), September 04, 1998.

Sounds just a bit steep to me. Do the tanks have lids included? Does the guy have any more 4 x 5 hangers? Are the hangers in good shape with retainers in good working order, not bent or rusted, holes and channels not plugged up with dried chemicals?

Problem with the plastic tanks is that they will take a long time (longer than metal) to come up to temperature.

It takes some practice to be able to process film in hangers with manual agitation so that you don't get streaks and uneven development from developer pumping in and out of the holes. You will probably ruin a few batches until you get the feel for it.

Certainly for large batch processing it is the way to go. However at that stage you would want to look for the cages which hold a dozen or so hangers so that you can lift them all at once.

Lots of film has been processed in that kind of equipment however, and you can do it. I just think you are getting short changed a bit on the hangers. I can see a dozen 4 x 5 and maybe six each of the other sizes for that price.

-- Tony Brent (ajbrent@mich.com), September 07, 1998.

I have tried trays and tanks (even tried a daylight tank for 4x5) with mixed results. I got scratches with all of them, but more with trays. Developing wasn't always even. Two years ago I bought the BTZS tubes for 4x5. Best investment I ever made. Good consistent results with no scratching and much cheaper than a Jobo. Don't bother with tanks. Get the tubes. A muc better system.

-- Michael Wellman (wellman@flash.net), September 22, 1998.

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