Switching from tray to drum developing

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I've recently purchased a Unicolor drum and motor base and have done some 4x5 and 8x10 film in it. I had been using Ilfosol-S and doing one agitation every 30 seconds in a tray. The first films that come out of the drum were overdeveloped. I took that to be a factor of the drums constant agitation. So I knocked off about 20% of the time. This seems to be doing the trick.. but the contrast is very high. If I take more time off the developing, I lose some to the shadow detail.

so... Is there a something else I should be doing? I'm thinking my next move is dilute the developer more. Whats the deal with the time then? Am I into a bunch of experiments? What are the storys of people who have gone down this same path.

Thanks for your help,

chuck k

-- chuck k (kleesattel@msn.com), November 25, 2000

Answers

I usually reduce development time by 10%, which has almost always been close enough to not need any adjustment. TMX wants around 5%.

I can't tell you anything about Ilfosol.

Generally, if you're developing film to the same CI in the same developer you'll get the same EI no matter how you agitate it; if you want to find out what's going on you'll need to do some carefully controlled test rather than using pictorial negs.

One thing to consider is that if a film/developer combination has some shouldering when using intermittent agitation, that shoulder may straighten up entirely when using continuous agitation. That _may_ be what you're seeing but with modern films the shoulder us usually _way_ above (higher density) than the range you'd actually be able to print.

Increasing dilution may help. Don't try to sneak up on it; use your original development time but double the dilution for a test. If that's ok then you're all set; if it's too flat then try 1.5X the original dilution.

Usually if you double dilution 1.5X the original time is a good starting point if the goal is to obtain about the same CI.

I often use D-76H 1:3 for a strong contraction using the 1:1 development time; HP5+ and TMX lose 2/3 stop and Delta 100 loses only 1/3 stop, but this is a _strong_ contraction, at least N-3.

-- John Hicks (jbh@magicnet.net), November 25, 2000.


Chuck I've used Ilfosol-S and the Ilfotech developers like LC-29. They are quite energetic like Kodak's HC110. You could try a pyro dev. but do wear gloves if your tray developing as it's quite toxic. Pyro responds well to the more frequent agitation of tray developing. And I feel is better suited to N-1, N-2 development without loss of shadow detail that hovers around zone II. However I have had good results with Ilfosol-S and 4x5 Delta 100 by diluting the dev. 1:14 with a N dev. time of 7min. Also you may like to consider Ilford's DDX dil. 1:4, again 7min. for N dev. Good luck,

-- Trevor Crone (tcrone@gm.dreamcast.com), November 26, 2000.

Chuck,

When using high-accutance developers, i.e. anything not advertised as "fine grain", you need to take advantage of the compensating effect to get full emulsion speed. Compensation occurs when the developer exhausts itself in the highlight (dense) portions of the negative, but keeps working in the shadow (less dense) portions. This effectively gives the shadows more development thus increasing effective speed.

Two things contribute to this: 1) a rather weak developer dilution, which delivers less developer concentration to the film thus allowing the highlights to use up all the available develper more quickly, and 2) minimum agitation, which keeps the exhausted developer in the highlighs from being replaced while the developer continues to work in the shadows. You can surmise from this that the effect is proportional to density: The less dense, the more actual development takes place, which allows fuller development of the shadows without excessive contrast. Since film speed is based on low-density areas of the negative, this increases emulsion speed while keeping contrast in check. All this means that developing in a drum with constatnt agitation and normal dilutions(thereby reducing the compensating effect) will reduce film speed and increase contrast accordingly. To get the greatest film speed and accutance without too much contrast, process in trays with long developing times and minimum agitation. I would recommend a return to tray processing. Hope this helps, ;^D)

-- Doremus Scudder (ScudderLandreth@compuserve.com), November 26, 2000.


Give your negative more exposure and then dilute your developer by 50% and give shorter development time in the drum. Because you are giving maximum agitation, which causes density to rise accordingly, you must give more exposure to the neg which raises shadow density. Then dilute your developer "and" cut down on your development time. This will bring down the density in the highlights (relative to the shadows) and still allow the shadows full density. You need to test for EI and development time because you are changing processes. Constant rotory agitation produces a very smooth negative with lots of specular detail throughout but can be problematic if you don't calibrate the system from camera exposure to development time and developer concentration. We can give you all sorts of off the wall answers but only calibrating the system will get you where you need to be. If you were getting good results from tray developing, why are you changing? I've used all the methods out there and like rotory processing best for what I shoot and how I like my negs but that for you might be different. James

-- james (james_mickelson@hotmail.com), November 26, 2000.

First off let me say hooray that you're using the Unicolr drums. There are a lot of people out there doing rotary processing but few of us still use the Unicolor drums. You've already got some great answers to your question and all I can add is to re-iterate the use of a more dilute developer to control the contrast. You diddnt mention the type of film you are using so I cant give any specific recomentdations but I can tell you that I use T-max 100 and I use t-max RS at a 1:9 dilution @ 75 deg F. for 11 min for an N process. This combo, other than the time, is pretty common and has been popularized by John Sexton. (that doesnt make it good or bad but it does give some starting points). A word of warning, the rotary agitation of a JOBO unit is NOT the same as that of our Unicolors! Dev times that people use for their JOBOs will usually not be similar enough to those of people with Unicolor drums to simply adopt without testing. In my experience the JOBOs are more vigorous even at the lowest setting that are the Unicolors. It almost seems like the Unicolor is halfway between tray processing and the JOBO rotary. Hope this helps!

-- Tony Mastres (mastres@id.ucsb.edu), November 28, 2000.


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