Please explain the importance of thorough washing

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How important is it to wash the prints? What happens if they aren't washed thoroughly enough? How does one tell if they've been washed enough?

Cheers, Lisa

-- Lisa Gerrard (lisazg@essex.ac.uk), October 21, 1999

Answers

I presume you're tlking about fiber-base prints. In either case, you *must* remove the fixer from the print, or the prints will stain and/or turn brown. A wash-aid such as Perma Wash or Kodak Hypo Clearing Agent will shorten wash times considerably. Follow the directions.

http://www.ravenvision.com/rvapeter.htm

-- Peter Hughes (leonine@redshift.com), October 21, 1999.


One might say that washing is the second step of the fixing process. During the fixing process, the remaining unexposed silver halides are converted into soluble complexes most of which are also removed from the emulsion into the fixing solution. These complexes are not so stable as to allow just leaving them in the emulsion. So the washing serves to remove them completely from the print. Also, the fixing agent is a sulphur compound which, given enough time, would react with the silver in the print, giving AgS, which is just what happens when a print is sepia-toned. Hence the brown stains on insufficiently washed prints. Finally, people wishing to make paper (not only photographic paper) archivally sound make a lot of fuss about acid remaining in the paper, because acid tends to destroy the paper in the long run. Most fixers contain acids which must therefore be washed out.

There are some methods for testing if the washing was sufficient, which actually all focus on the contamination of the print by residual hypo (the fixing agent). Test methods are describes in Ansel Adams's The Print and in several other books. These methods use easily available chemicals. You might also purchase ready-to-use test solutions. In either case, you put some of the final-wash water in the test solution (or vice versa), and look for a color change.

-- Thomas Wollstein (thomas_wollstein@web.de), October 22, 1999.


Sorry, there's a typo in my email, hope that hasn't caused too much chaos.

In reply to the first answer, no, I was talking about Resin Coated. Why?

Thomas, could you recommend a decent amount of time for which prints should be rinsed? I don't have a proper flowing thing, I just dump them in a tray and let the water flow into it via a rubber tube, then empty the tray about 3 times to make sure the print is getting a clean batch of water. Does this sound like enough?

Thanks very much,

Lisa

-- Lisa Gerrard (lisag@essex.ac.uk), October 22, 1999.


RC or fiber based paper -- it still needs a thorough washing to remove the products left in the emulsion after the paper is fixed. RC papers require a lot less time than fiber papers, but it must still be effective. Two or three dumps of water are not going to do it. The cheapest, but one of the most effective washing devices for either type of paper is a Kodak Tray Siphon, which uses your rubber tube, but gives good circulation of the wash water, and more importantly, removes the heavier fixing compounds quite well as long as the tray is not crowded with too many prints at a time. Poor washing will show up as stains of various kinds over time. It will show up immediately if you do any kind of print toning. I don't have an exact URL for you but Kodak or Ilford should both have good information on proper print washing.

-- Tony Brent (ajbrent@mich.com), October 23, 1999.

Go to Ilfords site and they have the best washing instructions on the web. I use a 16x20 tray and wash up to 6 11x14 prints at a time. I also use a hypo clear or other washing aid to help shorten the time and therefore amount of precious water I use to wash my prints. And may I make a suggestion? Learn to use a fiber base paper for your prints. Fiber base papers give you a much better print for most images you create. That is why most fine art printers use them. It takes a little longer to wash them but the tonalities are much better. James

-- james (james_mickelson@hotmail.com), October 23, 1999.


Although equally important (for the same reasons), washing RC papers only takes about a quarter of the time of washing FB papers. Better living through plastics...

-- Chad Jarvis (cjarvis@nas.edu), October 23, 1999.

Lisa,

RC prints wash out pretty quickly. The only problem with the tray is to make sure that circulation of the water is not inhibited by overlapping of prints. If you wash just one print at a time (or if you can ensure sufficient circulation around the prints by other means), I would think that five minutes of washing should be enough, or even more than that, particularly in view of your emptying the tray in between. You must, of course, ensure sufficient throughput of water, not just the water dripping over the edge of the tray. Many of my old RC prints which still look great were washed that way. If you use a slot washer, so I seem to remember from my Nova Washer's manual, you can cut the time down to two minutes. Less is not recommended.

-- Thomas Wollstein (thomas_wollstein@web.de), October 26, 1999.


I've got a nasty feeling brown stains are going to appear all over my prints shortly.....

Interesting that FB paper is considered to be better quality than RC - I had no idea, simply thought that RC was more modern.

Thanks

-- Lisa Gerrard (lisag@essex.ac.uk), October 28, 1999.


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