I'm going to final wash my fiber prints with a deep large tray (20x24), and two kodak tray siphons. I've read where some people use two trays, one above the other, and give the initial rinse in the bottom tray, and the final portion of the rinse in the top tray. I was wondering if anyone here has ever used this system, or kodak try siphons in general for final wash. Do I need to drill holes in the bottom of the tray to drain the hypo water from the bottom?
no, the idea that hypo sinks to the bottom because it's heavier than water is a relic of Fred Picker's attempt to reinvent physics. fixer is soluble in water; it will leave by whatever route the water leaves.
tray siphons work well for final washing ... i did this for years before finally getting a print washer. the disadvantages are that they require more attention, and they use way more water.
what i did was set the flow rate pretty low, and every five to ten minutes or so manually shuffle the prints so different ones would be on top and so nothing would be sticking together. i'd also take this opportunity to dump out all the water, just to guarantee complete water changes.
a two-tiered approach is a good idea too ... it will save time and water.
Hello. I started my darkroom w/ the Kodak siphons. I had my final wash tray above a rinse tray. But the best money I spent for my darkroom has been for a print washer. I bought an inexpensive Paterson 11x14 unit. I had trouble with regulating the flow w/ the siphons, and on occasion, the tray would overflow. The siphon does use more water. Actually, the print washer has overflowed from time to time. You need to watch your wash unit.
It's much easier to just soak the prints in trays and use no running water.
I've heard that Bruce Barnbaum does the soak method with complete water changes at some interval unknown to me--anyone know? Seems like a reasonable method that would save on water. Would some sort of water circulating pump make any difference (like a small submersible aquarium pump) to efficiency? Seems like it would disperse the fixer more completely than just letting the prints sit there.
I use a soak-n-shuffle method, moving the bottom print to the top every couple of minutes, and doing a complete water change every 10 minutes or so during the 60-minute wash time. The shuffle equalizes the overall exposure to water among the prints, and also acts to equalize the dispersed fixer within the water - at least in my mind. Multi-chambered print washers accomplish a similar function by giving each print its own little chamber. Similarly, the in-flow/out-flow rate of these print washer effectively does the water changes. I don't think there is a real dispersion-rate advantage to water circulation other than making sure the print surfaces have access to water into which to disperse the fixer.
"I've heard that Bruce Barnbaum does the soak method with complete water changes at some interval unknown to me--anyone know?"
the trick would be to change the water at short intervals at first, and then progressively longer ones. in the beginning you're rinsing fixer away. later you're drawing it out of the print fibers and emulsion by diffusion. the diffusion process happens faster when there's a higher concentration of fixer in the print than in the water. you want to replace the water with fresh water once it's taken on enough concentration to impede the process. by the end, the process will be happening very slowly no matter what, since there's such a low concentration of chemicals in the print.
as far as how long to do it for, there's no way to know without testing (using your prints, in your water). differences in tap water chemistry have a huge effect on wash times. and it doesn't seem like anyone understands the factors involved, so there's no reliable way to predict.
it's been shown that overwashing can be almost as bad as underwashing, for reasons not fully understood (but that may have something to do with your print acting like a water filter, and taking on all kinds of stuff from the pipes!)
I use a Kodak tray siphon for my final wash, 20 minutes of constant print shuffling with a water flow just enough to keep the siphon working, and a complete dump and refill halfway through. This is as part of an overall workflow that's a variant of the Ilford rapid fix/wash cycle.
If I recall correctly, at least one of the issues with overwashing is that there's some benefit to having non-zero residual thiosulfates.
I've found that Kodak tray siphons don't work well in "deep" trays. Just use a regular tray.
"If I recall correctly, at least one of the issues with overwashing is that there's some benefit to having non-zero residual thiosulfates."
this is true, and it's so potentially confusing that kodak doesn't even want you to know about it. a few details in this thread:
http://www.largeformatphotography.info/toning-permanence.html
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