Can deionised water be used instead of distilled?

[Tin Can]

Timely and I believe this answer more than the old thread http://www.largeformatphotography.in...l=1#post886851 which I read in early dawn.

I mix TF5 with distilled water AND drink it chilled, for 4 years and found no health issue. It also tastes better to me.

Photograghy Formulary suggests less odor from TF5 with distilled. I agree.

But I wash film in Chicago tap at 68 degrees, use no Photoflo, no squeegee and my film is spot free. I dry hanging over sink which is still wet. My dust level is low. Not perfect but I am fine with 'good enough' in many things.

Coffee is fantastic made with distilled. I cook with Chicago tap as I prefer to not live forever. Which is a very bad idea.

Actual deionzed water, such as laboratories use, can be as good as it gets. It's what we use to make microchips. But you can distill or deionize water and it can later become contaminated. And you can deionize water poorly. Just because it was once deionized doesn't mean it is forever clean.

With water we care about solid particles, dissolved solids ("minerals" and also metals), and dissolved gases. The first is only problem for photography if the particles are "big" (say over 10-100um). A simple filter is sufficient to remove particles. The second is a problem for photography only if mineral content is "high" (far beyond what would be acceptable for semiconductor mfg.). Some tap water has mineral content low enough for final rinsing film, but no tap water anywhere is good enough for chips. The third is really not a problem for photography.

Actually neither deionization nor distillation are required for good photography water. Good RO water should be fine for final rinse and for chemistry.

Both distilled and deionized water absorb CO2 and oxygen from the atmosphere over time. Neither is a problem for drying marks. If you really want the oxygen out, such as for mixing developer, I hear you can boil the water.

Neither DI nor distilled water is dangerous to drink. It is a wives' tale perpetuated by lab managers to keep people from drinking water in the lab. The absolute mineral content of even very hard tap water is minuscule and not enough to make a difference in ion depletion of the human body. In other words if drinking large amount of DI water causes ion depletion, drinking the same amount of tap water would have too. This is why sports medicine knows you need to add sugar and salt (on the order of entire teaspoons/tablespoons per gallon) to water intended for fluid replacement for heavy exertion.

[Drew Wiley]

Our tap water here is purer than bottled water, and certainly good enough for ordinary film developer usage. I generally used distilled only for final rinse or some
critical application, like matched color separation negs. What we get is snowmelt piped in from the Sierra. By comparison, many of the smaller coastal cities rely
on minor local reservoirs; and I'm convinced that those get filled by someone dumping Clorox right out of the bottle into them, and then full-strength Clorox right
out of the tap, plus some natural flavor enhancement, like essence of cow pie.

[Jac@stafford.net]

Our tap water here is purer than bottled water

May we nail your reputation and veracity upon that statement?

(I have intelligent family in SF. Wait for it. Wait...)

[Drew Wiley]

It's fact. SF gets their water from the infamous Hetch Hetchy reservoir, which broke John Muir's heart, then parks it in a few big local reservoirs; but its primarily direct snowmelt. EBMUD has a similar Sierra source, with extra storage locally. No river water. By contrast, one of the big bottled water companies simply filters its own non-melt tap water, adds some minerals back for taste. Another prominently displays a logo of the mountains and "bottled at the source". Much of it is actually bottled at a superfund site. The water does come downhill to the bottling plant, but...if the site of that is considered to unhealthy to even live at.... not saying it gets into the water, but ??? Our water quality if very well known. That's why there's such a squabble with the burbs, who want to get ahold of some of our water. Theirs is more a river cocktail containing trace amounts of all kinds of insecticides, fertilizers, natural contamination such as selenium, mercury. Sure it treated, but even if all the weird things were 100% removed, it would still taste like swimming pool water. Ours has no chlorine taste
at all. Along with the compromised air quality from all the refinery exhaust pulled by the air currents upriver, many of those satellite cities are nicknamed "Cancer Alley".

[Jac@stafford.net]

Drew, contrasting your water to the worst you can find is not a comparison.

[Kirk Gittings]

Hilarious. It's Drew's normal MO. Just as he contrasts the best traditional photography to the worst digital.

[Willie]

Water from the dehumidifier? Is it OK if filtered for dust and whatnot?
How does it compare with distilled for mixing chemistry?

[Willie]

Drew?
No fish poop in it?

[Fr. Mark]

Water from a dehumidifier ought to be good enough if filtered. It's basically rain water, which I'm surprised no one has brought up in this thread. Dehumidifiers have metal parts like the condenser coils, perhaps metal ions could leach in from those.

Mainly, I use filtered tap water except for developer concentrates. My problem lately is the crazy temp high of the "cold" water coming into the house and worse when I bottle it and it sits in the relatively untempered air in the basement. No running water in my darkroom yet.

I could imagine water with lower mineral content would be a good thing for final rinse for film. How you get there is up to you. I did not realize the big distinction between deionized and distilled. I also don't get how they degrade on exposure to air. Sure, they will pick up gasses, but no one said they were degassed in the first place (though elevating temperature does greatly decrease gas solubility in water) and they are sold in gas permeable polyethylene containers, usually. How are minerals going to get into the distilled/deionized water bottle if the lid is off? If the minerals are volatile enough to end up in the bottle, the temperature would be high enough to compete with a welding torch or better so I don't get that.

Deionized water is probably run through an ion exchange column which is not exactly a filter. Filter is a mechanical sort of thing for particles. Dissolved minerals are not particles by definition.

Another thought, my local tap water is chlorinated and to get rid of that and other chemical contaminants, we have a Carbon Block filter system at the kitchen sink. I get my photography water from that tap. it gets rid of particulates and chlorine, etc., but does NOT remove dissolved minerals much at all.

Chlorine is a gas and will eventually find its way out of the water if I were willing to have a bunch of open buckets sitting around, but I'm not and that would pick up dust. I used to use this method to dechlorinate water for goldfish in a fish tank to stop having to put the chlorine removal chemicals (reducing agents) in the fish water. I'd still be doing it but I don't have the fish anymore.

[blue4130]

Timely and I believe this answer more than the old thread http://www.largeformatphotography.in...l=1#post886851 which I read in early dawn.

I mix TF5 with distilled water AND drink it chilled, for 4 years and found no health issue. It also tastes better to me.

You drink TF5? Wow. Gin is as hard as I'll go.