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Its me again,
13x18 BW sheets, tray processing. What aggitation you recommend?
-- Martin Kapostas (firstname.lastname@example.org), June 27, 2001
If at all possible, use a tray one size larger than your negatives. I give 30 seconds continuous agitation at the beginning of development, by lifting one end of the tray. I work my way around the tray and lift each side for approximately the same amount of time. Then I give 10 seconds of agitation each minute thereafter, by lifting one edge of the tray--I work my way around the tray and lift a different edge each minute. For processing in PMK, I give 5 seconds of agitation every 30 seconds.
If you plan to develop multiple sheets of film, you will have to work out a system of continuously lifting sheets from the bottom and placing them on the top. This is the method Ansel Adams used. I have never had good luck with it--I get scratches on the emulsion and uneven development. I have read that there is a special tray that will allow you to develop 6 sheets at a time, each in its own separate compartment. Someone on this forum can probably direct you to a source for one. When I have to do multiple sheets of 4x5 film, I use four separate 5x7 trays and simply stagger the agitation. Works for me.
-- Ed Buffaloe (email@example.com), June 27, 2001.
Something that seems to work well is a "slosher," which has come up a couple times before in discussion. Some people make their own, though there is at least one available commercially (the makes of which escapes me at the moment). Phil Bard has plans for one on his a href="http://philbard.com/panel.html">site. I made one following his plans and have been using it to process 4x5 for about 3 years now and haven't stopped using it simply because it works well for me, even in PMK. In terms of open tray hand processing, it's easy to scratch up your film if you're not careful. I gave up trying to do 4x5 in that manner, though I do 8x10 that way on a regular basis (seems easier, for whatever reason). Some people have plenty of luck with it, though, so I wouldn't rule it out. Good luck.
-- David Munson (firstname.lastname@example.org), June 27, 2001.
Oops. It would be nice if this thing had a preview function so you could check your HTML before hand...
-- David Munson (email@example.com), June 27, 2001.
My agitation pattern is two-fold. First, I rock the tray by lifting and tilting side-to-side and then front-to-back. This is done throughout the development cycle. At the start of development, I "shuffle" the film pile based on the number of sheets I'm developing. Here, the bottom sheet is placed on top until all sheets have been rotated. I also shuffle the film every couple of minutes to make sure that each sheet receives fresh developer. This type of rotation is fairly easy to accomplish with a reasonable number of sheets. As a general rule, I try to develop no more that six sheets of 4x5 at a time. When using 5x7, I typically limit the number to four. My limit on 8x10 is usually two sheets. It is also crucial that you pre-soak the film in water before developing. This prevents sheet films from sticking together when they are placed in the developer and subsequently shuffled. In addition, use plenty of developer in a slightly oversized tray. Shuffling film becomes difficult if the tray is too small or the developer is too shallow. The standard developer to film ratio is about 100ml per 4x5 sheet or 100ml per 20 square inches.
Having said all that, the most important consideration in agaitation is consistency. Make sure your film has enough developer to avoid exhaustion and make sure fresh developer gets to the film on a regulat and standardized basis. Once you have a pattern that works, stick with it. I hope this helps.
-- Dave Willison (firstname.lastname@example.org), June 28, 2001.
Why is it that you don't hear too much from anyone on this site about the the old "dip and dunk processing method?" ie, using individual or 4-up metal hangers for the sheet film and thick Kodak black rubber tanks for the chemicals? (It's what some of us learned to use in photo school.) Andre
-- Andre Noble (email@example.com), June 28, 2001.
So what's a "slosher"? Is that anything like an old Mitchell Color Canoe??
Andre, in regards to 4-up racks in deep tanks...I do this daily and process somewhere in the range of 100-200 sheets a month this way. We have a small tank line, custom built in s.s. water jacket, 2 gallon tanks with floating lids & covers. All this in a s.s. sink with a water panel & chiller, and filters. We can run 28 sheets at a time, and use replenished TMAX RS. All in all, it's about 45 min. wet time, and then into a drier. We can average a few runs a day this way.
There's another lab, nearby, that has a similar tank line, only it's the standard 3.5 gallon tanks. You can run something like 96 sheets or so through that. At home, in my own darkroom, I run a 1 gal. line, with 5x7, 4x5, 2x3 and roll film. The beauty of a tankline, once you get it all down including replenishment, is being able to just walk in, pull the covers, and run your film. They get a bad rap most of the time, because people can't get the agitation worked out, or else they don't replenish well, or even have the load to make it work. Personally, I like the repeatability of a replenished developer. You can tweak it as time goes by, and monitor it as well. But, you have to be able to run film regularly through it to make it work.
-- DK Thompson (firstname.lastname@example.org), June 28, 2001.
This thread discusses the slosher concept in more depth. I think it's come up a couple other times, too, but I can't find any other old threads on the topic at the moment.
-- David Munson (email@example.com), June 28, 2001.
Mr. Thompson, that's what I thought, the relative lack of this type of handline tank processing is a matter of it's lack of compatibility with small volume/irregular use.
Seperate observation: after using "one size larger" tray size than film size as Mr. Buffaloe and others have suggested, I'm going to start using 8x10 trays bottom ribbed trays for my 4x5 sheet film - which is two sizes larger, technically. I find it too difficult to manage 4x5 sheet agitation in 5x7 developing trays with confidence. Anyone disagree in general?
-- Andre Noble (firstname.lastname@example.org), June 29, 2001.
Thanks Dave, I get it now. The Color Canoe was sort of a U shaped s.s. tray for doing c-prints. You could put it in water bath, and rock it back & forth for agitation. This way, you didn't have to have a whole tray full of chemistry, just enough to cover the bottom of the trough. For film, this wouldn't work too good though, I imagine the agitation would be wrong.
Andre, well at home I'm not running hundreds of sheets a month, but it does work good for me, and I mostly run roll film, and 4x5 through it. Despite all the problems people have with XTOL, I have found it to be almost the best tank developer I've ever used. I have run D76, DK50, Microdol, TMAX RS, all as repl. tank developers. Tank lines are alot like E6 lines....lab guys who run E6 lines will tell you about how E6 is almost a "living" process. They will insist that with one-shot, you'll never get it right... and to a degree, they're absolutely right. Now, I do run E6 in a Wing Lynch as one shot, and run control strips & plots...and you can stay in control, but there are very few things you can do for corrections. Same thing when it comes to b&w, only there's not as much that can go wrong as in E6. But if you only do a half dozen sheets a month, a tank will eat up alot of chemistry, unless you knock it down each session and store the chemicals. Then, maybe you can get 6 months or so out of it. I've done it both ways.
-- DK Thompson (email@example.com), June 29, 2001.