I've been out of photography for a long time now and I'm starting to get back into it in a big way. In the past (and recently) I've been hand rolling film a few reals at a time but the volume of film is getting to be too much for me to do a few rolls at a time. Is there a current standard for processing lots of film quickly (ie a cost effective machine, made by Jobo or otherwise). For that matter, do people even like the Jobo machines? Thanks to all in advance for your help.

-- Rodger Grossman (rodgerg@mediaone.net), July 31, 2001

Answers

Think about a deep tank system. A set of 3 gallon tanks will take a whole cage full of stainless reels, at least a dozen at a time, and the dev tank can be put into immediate re-use.
IMHO a rotary drum system has a worse throughput than hand souping in small SS tanks, due to the drying time of the reels. The one drawback is that a tank line needs a broom cupboard sized darkroom, a changing bag won't do.

-- Pete Andrews (p.l.andrews@bham.ac.uk), July 31, 2001.

John Hicks recently did some research with a Jobo tank and found that there is virtually no difference between the curves of film developed in a rotary tank and those developed with intermittent agitation in a hand tank. Developing times must be reduced. He wrote a brief article on it, which I have on my web site: http://unblinkingeye.com/Articles/Rotary/rotary.html.

-- Ed Buffaloe (edb@unblinkingeye.com), July 31, 2001.

Actually, the only reasonably reliable way I have found of putting a shoulder on the film is to reduce agitation - dilution etc on their own have never seemed to help in tests I have done. However, I must concur that the difference between continuous agitation and the usual (once every minute) does not change curve shape appreciably. I attribute this to the fact that most developers are reasonably powerful and so do not really exhaust appreciably in the highlights within 1 minute. I have found greatly reduced agitation (along the lines of once every third minute) does put a significant shoulder on the curve. Typically, this also has to be combined with increased dilutions for two reasons. One, since agitation is reduced, you want a long development time to ensure reasonably uniform development. Two, the increased dilution increases the rate of exhaustion in the highlights, the basis of the compensation mechanism. Other than this technique, I've found changing the curve shape for any film-developer combination to be remarkably difficult to do. Especially problematic is trying to get a long toe and increased contrast in the highlights - the only feasible method there seems to be using a staining developer, ideally with a long toe film. Cheers, DJ.

-- N Dhananjay (ndhanu@umich.edu), July 31, 2001.

Greetings,

People have different preferences, but I like the JOBO rotary processor for developing film. It's fast, consistent and very efficient. If drying time for drums and reels is important a hair dryer works very well in shortening that time to nothing. The problems I see with deep tanks, are the space they occupy and the massive amount of chemistry they require. If you're only doing B&W, using fairly inexpensive chemistry, that's not a problem, but doing E- 6 and C-41 can break the bank if you're not doing this commercially.

Perhaps you can find a local lab, school , or rental darkroom that has a rotary processor and give it a try before you buy. Good luck!

Regards,

-- Pete Caluori (pcaluori@hotmail.com), August 01, 2001.