Hard water printing

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I'm setting up my darkroom in a new town. The hardness of the water here is off the scale. There seem to be deposits of white film on everything tap water touches. The measurement of hardness is so high that water filter specs say they can't handle it.

I have trouble with water spots on negatives, and developing requires special care with photoflo using distilled water. I've pretty well solved that problem with negatives.

My question is: What special treatment should I give my prints to avoid water spots and white spots?

Soaking them, after washing, in distilled water occurs to me. Using photoflow occurs to me, but I'm wary of its leaving a while film. If I soak in distilled water, then for how long?

Has anyone had any experience out there with

-- Paul Arnold (osprey@bmt.net), September 11, 1999

Answers

I have hard water where I live and have the same problems. Before drying the prints I rinse them in bottled drinking water (rather than distilled water which is more expensive). I do this by putting them in a tray and filling it with bottled water and rocking it back and forth for a minute or two. This seems to work OK but I have not done any kind of scientific test. Since hard water is very alkaline, it can affect almost all the chemicals used in darkroom work, I always use bottled water.

-- Joe Miller (jmmiller@poka.com), September 11, 1999.

Greetings Paul, I lived and did lots of photography in San Antonio, TX with some of the hardest water in the nation and developed (no pun intentded) the following techniques: For negatives and prints a final soak with agitation in distilled water (or bottled drinking water, as long as it has a very low mineral content) of 2-3 minutes for negatives and 3-5 minutes for double-weight fiber base prints was adequate to prevent water spots (which are actually mineral deposits left behind when the water evaporates). For negs I always used a wetting agent, but never for prints, which I squeegee before drying. It is important to drain prints and negs thoroughly before putting them in the final soak, and you must replace the distilled water bath regularly since the minerals carried over from the tap water will, over time, build up in the distilled water bath. This is especially important for negatives. I you have spots on your negatives after the distilled water bath, it is too old! Hard water, especiatlly if calcium carbonate is the mineral component, which changes the pH, can influence (increase) developer activity. I got by with mixing HC-110 with tap water and re-calibrating my developing times (they were shorter on the whole) but many developers perform better when mixed with distilled water. Stop and fix may also be affected. Usually the working life of the two solutions is shortened somewhat when mixed with hard (slightly alkaline) water, but this is not normally a concern. Washing prints and negatives seems all right in hard water but if you have iron components, etc., you may want to use some kind of charcoal filtration to avoid discoloration, particularly if you tone your prints. This would only be necessary if you have actual problems. Don't buy stuff you don't need. I found the distilled water soak to be all that was required for 90% of my work. Experiment and see what you situation requires. Hope this helps. Regards, ;^D)

-- Doremus Scudder (ScudderLandreth@compuserve.com), September 12, 1999.

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