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Ben Calwell
4-Oct-2004, 06:24
Well, after nearly 20 years of flawless (no scratches) tray processing of 4x5 Tri-X (old), I'm getting my feet wet with the new 5x7 Tri-X, and I'm not happy. I shuffled through a group of three 5x7 sheets last night for my normal time. When I turned on the lights I noticed long, faint scratches along the 7-inch length. This never happened to me with old 4x5 Tri-X. I used the same development routine I've always used: pre-wet for several minutes so the sheets are wet and slick, then transfer them to the dev. tray (PMK). I think what happened is, I didn't keep the sheets absolutely squared up with each other, so that when I pulled one sheet from the bottom, a corner would cut into the surface of the sheet below it. In other words, when pulling a sheet from the bottom, don't pull it at an angle to the ones below it. These scratches never happened to me with the old 4x5 Tri-X. Is the new Tri-X emulsion more delicate than the old stuff? Other than processing one sheet at a time, I guess I'll have to spring for a $200-plus Jobo expert drum.

William Blunt
4-Oct-2004, 07:46
Ben, Are you developing the film emulsion down or up? I find emulsion side down works best for me. I find no difference in the new tri-x , as far as how delicate the emulsion is. Good luck

clay harmon
4-Oct-2004, 07:50
I've been switching over to tray processing from using the jobo, and I have found that I can tray shuffle 3 or 4 10x12 sheets with nary a scratch, but trying to do 7x17 with what seems like the same technique leaves me with lots of scratches. I think you are onto something in that the longer skinnier formats are harder to 'keep square' in the tray. I am thinking about using some suction cups with little dowel rods in the middle of my tray to make some compartments in the 16x20 tray whenever I do 7x17 processing. I also generally process with the emulsion side down, which I gather most people do.

Gem Singer
4-Oct-2004, 08:12
Hi Ben,

I was experiencing the same problem. Recently, I began using both 5X7 and 8X10 sheet film and developing these larger negatives in trays. I had been developing my 4X5 negatives, using the dip-and-dunk method, for many years, with no scratches. But dip-and-dunk tanks that could handle 8X10 film would be out of the question for me.

At first, I was using 8X10 trays, with one liter of solution. Shallow depth and limited room to shuffle the films seemed to be the cause of the problem. I purchased a set of 10X12 trays from Anthony, at Fine Arts Photo Supply, and now use two liters of solution. I still have to be careful when shuffling those wet negatives, with their soft emulsion, but using larger trays containing a greater amount of solution, has solved the problem for me.

Ralph Barker
4-Oct-2004, 08:53
I think there are several factors that come into play with tray processing, Ben. As has been suggested, processing emulsion side down helps, as does using larger trays and correspondingly sufficient chemical volumes. I use 8x10 trays for 4x5 (1 liter of solutions), and 11x14 trays for 8x10 (2 liters of solution), keeping the film stack "organized" into one corner of the tray during processing. The larger the film, however, the more fiddly the process. I've found I can stretch to about 8 sheets in a 4x5 stack, with 6 or fewer being preferred, but I limit the 8x10 to 4 or 5 sheets.

One other factor I've noticed is that occasionally I get a box of film the sheets of which are difficult to separate during loading. My assumption is that the cutting process has left microscopic burrs on the film corners. Those tiny burrs might cause problems during processing, as even slight offsets in the stack would result in a greater potential for scratching the emulsion of the adjoining sheet. Thus, I'm thinking of adding a burr-check step to my holder-loading process, with the idea of trying to "burnish" the film edges at that stage of the process.

Ben Calwell
4-Oct-2004, 08:59
Thanks for the advice, fellows. I use 5x7 trays for my 5x7 film, thinking the smaller size would help me keep the sheets "corralled" in the tray so they won't float all over the place and get cock-eyed to each other in the tray (this has happend to me when I use larger trays). My foolproof (for me, anyway) method for 4x5 is to use glass Pyrex bread pans that are slightly smaller in width than the sheets. This keeps them square to each other and also keeps them from sinking to the bottom. I'll also try emulsion down next time. Thanks again.

Larry Gebhardt
4-Oct-2004, 09:24
I have had scratches due to the notchcodes. I suspect that the punch left a slightly jagged edge. I think the film was the new Tri-X. I had trouble eliminating these and other scratches so I gave up and went to the Jobo. I also didn't like standing in the dark for that long hunched over a sink, I found it boring and it hurt my back, so I didn't try to hard to fix the scratch problem.

ronald lamarsh
4-Oct-2004, 10:22
I have experienced this horror many times in 4x5 and 5x7 and I know that it is just my sloppy technique. My cure is to develope my films singley which is very laborious but VERY safe or use a tray that i divided into four sections using acrlyic that has been "swisscheesed" for dev circulation but keeps the films separate......it works great. I believe that somewhere on the net you can buy a plastic device that fits 4 4x5's or 5x7's into an 11x14 tray. Its cheaper than a jobo

Darin Cozine
4-Oct-2004, 10:47
If the scratches are perfectly straight lines running the length of the film, it may be your film holders scratching the film.

windpointphoto
4-Oct-2004, 12:12
You will find that by using larger trays your development will be more even. It's also easier to handle the sheets. IMO.

Carl Weese
4-Oct-2004, 12:37
Along with using a larger tray and plenty of solution, tip the trays forward (a piece of 1 inch PVC pipe works well). Gravity helps keep the stack of sheets at the front of the tray. I routinely do 10 8x10 sheets in an 11x14 tray with 3 liters. For 7x17 I do up to 8 sheets at once in 4 liters with a 16x20 tray, and for 12x20 I do up to six sheets in a 20x24 tray with 6 liters of solution. Be sure to pre-soak each sheet before adding the next one, and keep everything lined up well as you shuffle the sheets. And don't rush: once through the stack every 30 seconds is fine with the long PMK processing times.---Carl