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Yaakov Asher Sinclair
21-May-2000, 17:56
The water here in Jerusalem is very hard. The bottom of our kettle is caked wit h white mineral deposits. Should I use distilled water to develop films, or may be bottled water? Thanks Yaakov Asher Sinclair

Trevor Crone
21-May-2000, 18:19
The water here in London is also very hard Yaakov.I don't think you need to go t o the added expense and trouble of using distilled/bottled water to dev.your fil ms if you are using proprietary developers.The only precaution you realy need t o take is to use some form of water filter to remove any foreign matter in the w ater that may stick to the film,a good cheap one is made by Paterson or somethin g more upmarket is the Ametek range of water filters. If you are mixing your own developers from formulae then it is best to make-up s tock solutions with distilled water to prevent precipitation. Regards,Trevor.

M.
21-May-2000, 18:23
Use distilled water at least for developer and final rinse in Photo- Flo. It doesn't cost all that much in amateur quantities. Put a good filter on your faucet head for washing the film.

David_892
21-May-2000, 18:40
Definatly use distilled/filtered water for atleast the developer, but I'd use it for the fixer too. Ah, one of the benefits of living in Scotland - nice soft water.

james mickelson
21-May-2000, 20:44
Tell me now? What are the true benefits of using "distilled" water as opposed to "non-distilled" water for processing film? What happens if you don't use "distilled" water? This is a test in logic. James

james mickelson
21-May-2000, 22:28
I don't know Dan. I kibitz with quite a few veteran darkroom workers and they all have their own methods when it comes to mixing up chemistry and processing film and paper. But I just don't see the difference in any of their finished images. None. I'm not saying that anyone should change their working methods. Not at all. What I'm saying is that, on these newsgroups/photo forums I keep hearing "you have to do this or that or your stuff will look like shit". I don't buy it. You are a very good photographer and I like your images. But Joe Amateur doesn't need to go out and buy distilled water or get a filter system in order to get the same results as you. As long as there aren't any gross impurities like leaves and dead fish, most water will give excellent results. Except for the big commercial labs it wasn't until the 60's that people even thought about filtering their water. I just think it is a waste of good processed water which only adds to the expense of photograpy to keep telling the amateur they have to use distilled water to get decent results. I don't use processed water and my results are great. Smooth tonalities, crystal clear blacks and clean high values. And unless you have extreme pH differences from the rest of us, the ppm impurities in your water are zilch compared to the amount of chemical you are introducing anyway. Too many purists sing the same song when it comes to mixing chemistry and processing materials. Photographers in the rest of the world don't have the luxury of filtered water and they produce consistently great, clean images. James

John Hicks
21-May-2000, 23:23
Use distilled water for the final wetting-agent rinse, but I wouldn't worry abou t the tap water (as long as results on film are ok) unless you're getting precip itates in the solutions or other oddities.

Struan Gray
22-May-2000, 06:48
Dissolved minerals can affect developer activity, among other things, but the real problem is that in most areas with hard water the mineral content varies with the seasons, the temperature, and with how the local water authority routes the water through it's domain.

Photographic chemistry is not about being accurate, but it is about being consistent. If your water supply has a constant mineral content you can adjust your processing and exposure to compensate for any effects it may have. With a varying mineral content results can become unpredictable, and unless you like re-shooting negatives it makes sense to eliminate unpredictability, particularly if the cost is low as in this case.

Bottled water often has a high mineral content (it's part of the sales pitch). Expensive brands like Evian work hard to keep it constant, but cheap ones vary just like your tap water so distilled or deionised water makes more sense. I don't know about Isreal, but in most of Europe it can be bought from pharmacies in multi-gallon sizes for not much money.

Doremus Scudder
22-May-2000, 08:34
I lived and worked in San Antonio, Texas for a few years, which has some of the hardest water in the States. The entire city is supplied by wells drilled in limestone formations so the calcium-carbonate levels were really high. I found that I could use the tap water for mixing developer, but that the added alkalinity did increase the developer activity somewhat which had to be compensated for. The important thing is to be able to get consistant results. If you have a water supply with consistant mineral content and don't do much developing anywhere else then you should have no problems. Of course, using distilled water certainly won't hurt, and you can duplicate the results world-wide. Do, however, use distilled (not "bottled" or "purified") water for your final rinse before drying the film (I mix my photo-flo with distilled water and soak the films with constant agitation for at least 2 minutes). Softened water is good for washing, being even more efficient because of the salt content, but will leave nasty crystals when it dries if you don't rinse with distilled water. Hard water usually takes a little longer to wash with, depending on the exact content. If you still get water spots on your film, increase the time in the distilled water solution. Remember, if you develop large batches of film at a time, to change this solution regularly, as it can become saturated with minerals and start leaving water spots as well. Hope this helps, ;^D)

M.
22-May-2000, 17:41
I'd rather do just about anything instead of spotting dirty negatives, especially it if could have been provented. That's why I recommend always using distilled water in the developer and final wash. It has nothing to do with chemical reactions. Mitch

james mickelson
25-May-2000, 03:45
If your water has particles large enough that you have to spot your prints after processing, even given enlarging 35mm to 16x20, I would contact your local Water Quality Control Board. All minerals such as calcium, Cabonates, sulfates, and iron are in the molecular state so if you are seeing spots it isn't because you are using tap water and the mineral content is high. When you use a photo flow type viscosity lowering wash aid you should come out with pretty clean negs just using tap water. I live at the very end of a 700 mile water delivery system and have some of the highest loads of minerals in the country outside of Texas and I don't use anything but tap water. And I never see any hint of particles. I think it is a wives tale that has been passed along through the years and will continue to be a part of the photographic folklore forever. If you use distilled that's fine but I question the need for it. You have to add a hell of a lot of sulfite to developer to get the increase in activity people talk about. So why is the difference between water in New York City and Texas so problematic that people have to use distilled water to keep consistent processing characteristics? And have most of you calibrated your processes so well that a 1/10th f-stop speed difference is so great as to be noticed? I question that assumtion. James