Water Quality

[aaron2]

Would be glad to hear people here talk about requirements of water

for processing film & paper (traditional or alternative process); How

to test for your (or where to find out information on) water purity,

ph & hardness, etc. And also remedies to existing problems.

 

Thanks.

[photobyalan.com]

I use distilled water for mixing all stock solutions and working solutions. I use tap water for washing. Distilled ONLY for photo flo solution, final quick rinse in distilled water after the photo flo.

 

Distilled water isn't very expensive and gives me complete peace of mind that I have no issues with water quality. Since the water jugs sit in the darkroom, and the darkroom is 68 degrees F, I also know that I never need to check the temperature of working solutions after I mix them (I do test occasionally, just to be sure).

[richard_ilomaki]

Aaron;

 

I have been using tap water in various cities for mixing photo chemicals for over 40 years, and water from a country well for 3, and have yet to experience any difficulties attributable to water quality. This includes some cities in China and other "3rd world" places.

 

I once heard someone from Kodak say that if you can drink it and survive, it is OK for just about any photo use. Am exception would be the need for distilled or de-ionized water for final rinsing with wetting agent, and for clearing of platinum using EDTA or other metal chelating agents. IMHO using anything other than tap water from any major city is not needed.

 

Unless you have unusal hardness nothing needs to be done. Check the Kodak website and do a search for "water quality"

 

Cheers

[photobyalan.com]

I should have mentioned that where I am the water comes from wells and is very hard with high iron levels. If I was on reservoir water, I'd be a lot less concerned about using it for mixing working solutions.

[aaron2]

Thanks for responding.

 

So what water hardness is ideal for processing? If too soft or too hard, can anything be done about it? Need one worry about ph too?

 

Thanks again.

[robert_davis2]

Last week when I was checking Kodaks datasheets on E6 it claimed something like 1000 ppm of hardness or less. That's almost mud. Somebody claimed the chemicals are formulated to use the buffering that's in tap water. OTOH most B&W formulas are I think designed to be made with distilled water. I use tap water for everything. I think about distilled water for washing film some times but my film dries fine so I forget about it. I don't know where you're located but in North America you should be able to call the local water company to get a water report. The local one is actually on the web here in Toronto. It also depends on how your area gets it's water. You may have seasonal changes to deal with.

[robert_davis2]

If your water is too soft then you could add chemicals. Relatively easy but I doubt you'll ever need to. If it's too hard then either use distilled or blend your water with distilled .

[richard_ilomaki]

Aaron;

 

If you call your Culligan Man-really, and ask trhem, in the intersts of selling a softening unit, they may well help.

 

If you can get hold of some SodiumTripolyphosphate and add a few-5- grams/litre, that should tie up most of the iron. Unfortuantely STPP is usually available in boxcar quantites for detergents etc. Water softeners available in supermarkets also can do just as well.

 

Cheers

[michael_sherck]

My house has a well and my water is hard, mostly iron. I use it for everything except the final rinse in Photo-Flo, for which I use distilled water. Rinsing just in my well water occasionally leaves white mineral spots on the negatives, which is why I switched to distilled for that step.

 

I have a water softener but have switched my darkroom to unsoftened water: tests indicate that washing prints in the hard water takes about half the time they take to come clean in the softened water.

 

Mike

[donald_miller1]

The problem with softened water or even water with too little in the way of mineral content is that it causes an excessive softening of the emulsion layer on the film. This can cause difficulty in washing as already mentioned and also increased chance of damage to the emulsion layer. 1000 ppm is the equivalent of 58 grains of hardness. That would be extremely hard. Since hard water normally is considered such when the hardness level reaches 7 GPG and above. There is one additional consideration about softening water and that is the ion exchange that occurs within the softening process. Sodium is exchanged for calcium and magnesium. The sodium ions that are exchanged for the ions of those minerals are in the form of a dissolved solid. Therefore what one accomplishes is the removal of undissolved solids and the corresponding introduction of a dissolved solid. This dissolved solid would very probably remain in the emulsion layer of the film and if of great enough concentration cause a subtle cloudiness in the image. The only true mineral removal (both of the undissolved and dissolved solid nature) occurs in the reverse osmosis treatment of water. However as I mentioned earlier the total removal of mineral content leads to a greater softening of the emulsion layer and the inherent problems that then occur.

[rick_jones5]

Alan Babbitt - would you expain how you raise the temperature of your distilled water to mix stock solutions (assuming some are from powder)and why you rinse your film with distilled water AFTER the photo flo treatment? I would have thought that would have defeated the whole purpose for using the photo flo.

[tom_westbrook]

Interesting, Donald. Do you know if deionized water is a better option than standard softening? I've been thinking of getting an RO or RO/DI unit to save some money long term over buying distilled water for darkroom use. Or am I just as well off with a simple particulate filter (like 5 microns or so).

[eugene_singer]

I got tired of struggling with the quality of the tap water in the various locations where I set up my home darkrooms. Now, I only use distilled water, that I purchase at Wal-Mart($0.58-gallon), for mixing my film developer, stop bath, and fixer. I also use it for mixing my paper developer. I use 5 micron filtered water to mix the stop bath and fixer for processing paper. My film and paper is final washed in the filtered water. I use distilled water for mixing the final Photo Flo rinse, for film. It is not absolutely necessary to give film another rinse in plain distilled water after the Photo Flo bath, but some do it to rinse off the Photo Flo.

 

 

I use a one liter Pyrex kitchen-type measuring pitcher for mixing powdered developers. I found it to be ideal to use for heating distilled water in a microwave oven. The developer powder dissolves very quickly if I heat the distilled water to 105-110 degrees F, stir in the powder, then re-heat to 120 degrees F. I pour the the freshly mixed developer into a tightly sealed storage bottle and allow it to cool down slowly (usually over night). All of the chemicals are then tempered to 68 degrees F, when ready to use.

[pat_kearns1]

Aaron, I can't really say if the ph has anything to do with it but the tap water I use runs about 7.8 - 7.9. The only time I have a problem is using HC-110 dilution B at 68 degrees with Tri-x. I have to shorten development about 1 minute otherwise my film is a little over developed. It doesn't happen with Plus-X. When I shoot Tmax I use Tmax RS without problems. Go figure.

[aaron2]

For a while, I've been getting white spots on my negatives. Distilled water with Photoflo as a final rinse didn't help. I suspected water impurity. Recently, pipes from within the wall began to leak. As it turned out, greenish stuff and other particles were found to have corroded the pipes almost completely. The same water transported through it must have been the cause to the negative defect. What are these stuff? Would the impurity in this case also defeat the purpose of archival processing of photographic materials?

 

Thanks everyone for sharing in this discussing. You've brought up many interesting information.

[photobyalan.com]

Rick

 

Promise you won't laugh.

 

I've got a 5-liter plastic paint pail (no handle) that I got at the hardware store. It just fits in my microwave. 10 minutes at 100% power raises the temperature of 3.9 liters of distilled water to 104 degrees F.

 

I just realized I'm using Farenheit temperatures with metric volume measurements...oh, well, rules are meant to be broken!