purified water for film development development? good/bad?

[jp dobrin]

I've always used tap water for all parts of the film developing

process.. and my results have been fine. But then again I'm a student

and have only used D76 developer with many diff types of film

 

I've heard of some people using distilled water for latter stages of

the development process.

 

The only reason I ask is b/c I have easy access to purified water. My

hobby is keeping saltwater (reef w/ live corals) aquariums, which

require purified water. So I have a 4 stage reverse-osmosis unit with

a Deionized attachment at the end.

 

I'm plan on being more precise with my film development process (ie

using better film developers) and generally want to improve my results.

 

Should I use purified water for any/all of the development steps where

water is required? or is this just a waste of time?

[dean_tomasula1]

It's always best to use distilled water for EVERY step of the development (including mixing chemicals and washing). You never know what is lurking in your water that can be harmful to your film/paper. Purified water is ok, but distilled is better. The distilling process apparently eliminates more of the impurities than filtering does. Distilled water does not cost that much and in the long run, aren't your photos worth it?

[red_jenny]

I just do a final wash in distilled water so as to avoid hard-water marks.

[silent1]

Distilled or DI water will never hurt your process, and is absolutely consistent (especially if it's good enough for delicate salt water aquarium ecosystems). Consistent is good, both for fish and for film. Assuming the DI water doesn't cost you much, go for it. If it's a lot cheaper (don't know what it costs to run the equipment), it'd probably be fine to take the water off after the reverse osmosis and before the DI attachment.

[jay_de_fehr]

Distilled water is particularly important for making up stock solutions, like your D-76, Dektol, etc., because impurities can dramatically affect the keeping properties of your stock solutions. Purified water is much better than most tap water, as I'm sure your aware. Wether or not the use of more pure water will make a difference in your results is anyone's guess, unless you're having problems with water spots, or other impurity defects in your negatives. Other than the keeping properties, or dirty negatives, it is very unlikely that you'll see any obvious difference in your results, but given the choice between tap water and purified water, I would choose the purified water every time. Good luck.

 

Jay

[lol1]

I'll second Red -- I always give a final rinse in distilled water (and 2ml of wetting agent) because I live in a hard water area (London) and I'm guaranteed to get drying marks if I don't do this.

[jp dobrin]

thanks for your responses.

 

Since I have access to one of these units it seems like it can only help to use the purified water.

 

just in case anyone wants to know.. these RO/DI units are fairly expensive (several hundred dollars initially). They do waste a lot of water.. but operating costs are very low. But every so often you need to replace the filters which can be expensive.

 

I guess I'll go ahead and try it!

[ronald_moravec1]

I did an experiment severals years ago, D76 mixed with distilled water. T Max grain was hugh.

 

A fellow in a nearby town didn`t believe me. He always ran the most beautiful T Max 400 I ever saw. He threw away the model shoot and the rest of the unused developer.

 

Try your luck and experiment first.

[sam_spade2]

Hi Jean. I'd agree with Jay as after years of paddling around in my dark watery environment I?ve come to the conclusion that ?Anything?.Anything? is better than tap water; hey, I don?t even drink the stuff, but then again, I don?t use a stop bath for films or prints, just plain filtered water as in Brita, or whatever was on sale at the time. Paid ?7.00 for a jug type water filter, works great tastes great. The fact is, that whether or not you live in a hard/soft water area is not really the point, most developers have built in (or so I?ve been told) sequestering agents that are supposed to hold the nasty bits at bay. The point is; does it work? I?ve no idea? But if it does then why are we all using distilled and or purified water? Me, well, I don?t take the chance: I mean; do I/you really want to find a really nasty drying mark on that great, once in a lifetime neg? No, none of us do, so prevention is better than cure. Distilled is best, but double distilled is king, well almost; Nano is, well, EXSPENSIVE! So; if you have a free-ish supply of ?purified? and as you?re running a Rev-Osmosis set up it should be, then give it a go on a test roll. I?ve used it for years, well up until Boots tried to charge me ?3.00 for 5lts! Now I use the jug filtered water for all mixing and washing, though my final rinse is always in distilled. Then I hang the film up and give it a good spray with a small Woolies cheapo garden spary gun (no metal parts in it mind) filled with distilled water and then leave it alone to dry. No marks, no spots, just nice clean negs. Try it, it might work for you: for as with all things in photography, no one way suits everyone. Or, as the song goes?. ?You like potato and I like potahto, you like tomato and I like tomahto;

 

Hope this helps.

 

Take care.

B.

[lex_jenkins]

When my darkroom was in an area with well water from a limestone cistern we got actual chunks of stuff out of the tap. I used, at least, a filter system and finally mixed up my concentrates and stock solutions using distilled water.

 

The only obvious difference was the absence of scratches on my negatives.

[chris_waller]

I've never used distilled water because developers are buffered on the assumption that they will be mixed with tap water which varies in acidity/alkalinity. But I do filter the water through an Ametek 10 micron filter to take out the particulates.

[robert_grasing]

Robert Chapman has written about this several times in the last 20 years in Darkroom and Creative Camera Techniques, now Photo Techniques. His opinion: tap water is usually fine, chemically. (Chapman has a PhD in chemistry from Yale, works in photo-chemistry).

 

There is something else to consider. From time to time, some people have claimed that they've gotten better results with developer mixed with tap water rather than distilled. 'Better' in that the grain was noticeably finer. In fact, there was a letter to Chapman about this, but he had no explanation for this phenomenon. It sounds doubtful, but over the years I've heard other, similar reports.

 

I don't have access to distilled water, I've always used tap. But as an experiment, you might like to try both and see if there is a difference.

[winfried_buechsenschuetz1]

As a compromise, you can boil your tap water for 10 minutes or so, and then let it rest over night. Carefully pour off the upper half to mix your chemicals and use the rest for your flowers. If you let the water rest in a transparent jar you will be surprised what will collect on the bottom half. I have made stock solutions (Emofin) with that method for some time years ago and never had any problems.

 

Concerning film rinsing, I always use a rinsing agent (Agfa Agepon but any brand will work similar) and never had any problems with water marks etc. I never used a squeegee and never had drying stripes on the films. There have been reports that the rinsing agent will collect on the reels etc and leave a layer of gunk there. I have always rinsed everything carefully after processing (even before I heard of that) and never had this problem.

[edward_zimmermann]

Other than cost there is NO reason why not to use Aqua Dest for photographic developers. Reports that results of grain were better (or worse) with tap water I suspect were derived from the failure in the correct pH buffering of the developer and would not be duplicatable in other areas--- not even perhaps in the same area as different water qualities enter the network. With most properly designed developers, however, its not demanded but boiled and decanted tap water can, in general, be used. The cost of energy and effort to boil and decant water, however, might be in excess of the current costs of Aqua Dest which are typically not double distilled ($$) but (inexpensively) demineralized by reverse osmosis and deionized water from the communal water system (tap water). In preparing developer concentrates using Aqua Dest it still makes sense to boil water to reduce oxygen content.

<P>

Aqua Dest or even purified water, however, is ill-suited for rinses (other than the final) and washing. The varous ions in freshly flowing tap water are important to the wash cycles.

[jim_baughman]

Distilled water is easily and cheaply obtained from a home dehumidifier. The Sears unit in my basement easily produces a gallon or more a day in the humid summer months. If you keep the condenser and the drip pan clean it should be perfectly usable and almost free.