Filters primarily remove solid particles, and dissolved material, be it
minerals (e.g., calcium ions) or gasses (chloride ions) are not solids.

Those filters containing sufficient activated charcoal can remove some
dissolved gasses, such as chlorine.

Since most photographic solutions are buffered, it is unlikely that
something like chlorine will be dissolved in the water in sufficient
quantity to affect the pH very much. Some people have trouble with
changing from one water to another, though I never noticed it, even when
the taste of the water was extremely different from one place to another.
I assume (without knowledge) that their problems are perhaps due to
different ions in the water, and not chlorine or its pH. But since it
never bothered me to use municipal water, I never investigated it much.

Solid particals make a mess of negatives, especially small ones such as
24x32 mm ones on 35 mm film. Hence I use a 5 micron filter on my tempered
water. I mix my PhotoFlow with dehumidifier condensate that I filter
through a cotton ball (used one shot). But everything else I use just
plain municipal water.

Were I to use solutions containing precious metals (e.g., platinum, gold)
I would use distilled water for them. When I was doing Cibachrome (now
known as Ilfochrome), I was advised by Ilford to not use distilled water
as it was too soft and the wet emulsion was too soft. They recommended tap
water, which is usually harder, as the most practical for processing their
stuff.

I never have and have no noticable issues.

Course I'm somewhat nearsighted :)

But in my part of the country the water is also very
pure (no pollutants or finer particles/sediment to
filter out, but is chlorinated and fluoridated.) I
would probably worry about filtering water that isn't
so pure.

 Go to the local big box hardware and look over the various filters. It's
pretty easy to find one that'll handle chlorine. Can't hurt to get rid of
it. If you aren't in a hurry other methods then filtering will get rid of it
to but filtering is relatively cheap and painless. If you're setting up a
new darkroom then consider just putting the filters into the water supply.

   Nick

I was using well water and I used a Brita (or pur, same thing) which
cost me $30 for the kit that comes with a filter that screws onto the
faucet and I replace the filter once every two months.  The water
output is low when its running so unless you have massive water needs
(and need them quickly) this may be a good choice.

Another thing i've done is used an aquarium charcoal filter you can
get at Petco/Petsmart/Pet-whatever.  They are moderately tall, narrow
tube-like things with a faucet end and a tube end.  This is relatively
low water output (and somewhat hard to control the temperature as the
water has to filter through about an 18-20" tube first, but I got used
to it and it worked fine for me... Its basically a tube packed full of
charcoal.

Cheers,
-sd
http://www.zoom.sh

Greg -

Many years ago, I did Cibachrome printing and had acquired a decent level
of competence.  Then my wife convinced me that we needed a water
softener.  I was never able to recalibrate the color balance after the
water softener was installed.

I also used to do E6 work.  I didn't notice any difference in that
process before and after the water softener.

Then, two years ago we moved to our new home.  Because we knew that the
water supply in the new place had a significantly higher iron content, we
decided to go ahead with a water softener.  After constructing the
darkroom in the new home, I found that there were some discernable
changes in my black and white work that I attributed to the fact that I
was dealing with a different water source, but I was able to recalibrate
fairly quickly.

So my point is that making changes in your water supply may result in
discernable differences in the results you get in the darkroom.  But my
experience is that in monochrome work this is a relatively minor nuisance
that you can quickly recalibrate for.

In the old place, I used filtered condensate from the dehumidifier as
final rinse water in processing film.  We don't have/need a dehumidifier
in the new place, but we did choose to install a reverse osmosis drinking
water filter.  I'm using that water as my final rinse.

Second message - installing a filtration system can be beneficial.

I have done E-6, C-41, and B&W processing for nearly 30 years with an older
municipal water supply, very hard water.  I never noticed a difference in
results between my initial, unfiltered usage and later.  For the last 20
years, I pipe 5 micron and charcoal filtered water as well as straight tape
water into my darkroom, using the filtered supply for mixing chemistry and
film processing/washing.  My main concern is not dissolved chemicals but
rather the high quantity of sand and grit in the city water supply, which I
can adequately filter with this setup.  I use a normal in-line canister rig
with an appropriate filter.

On 11/24/2004 6:14 PM Gregory W Blank spake thus:

A local culinary guru 'round heah', Narsai David, has said that all one need
do to remove chlorine from drinking water is to let the water stand for about
5 minutes; the chlorine just evaporates, for the most part.

Dunno if this is true or not. Anyone with more chemistry smarts can confirm or
deny this?

(Here's a thread from a web site discussing the subject:
http://www.chataboutphotography.com/Chlorine_effects_on_chemicals_solutions-3033
335-674-a.html)

Greg,

  I'm going to go against the flow of the other post.  I use demineralized
water for all developers, including dilutions, bleaches and fixers (not to
mention final rinse).  My reasoning is, if you want consistent and
repeatable results, then why chance it to something like the water.  Demi
water is cheap.  I strive for the most consistent processes to maintain the
repeatability of the calibrations I so painstakingly worked through.
Especially with color processes.  It may not amount to a hill of beans in
actual differences, but at least I can say - It ain't the water, so it's
gotta be me.

 My two cents worth.

Jim

Gregory W Blank <gblank@despamit.net

 Free chlorine in water is an oxidizer. I doubt the amount
present will be detected in your day to day work. Perhaps distilled
for your more sensitive solutions; developer being one.
 De-chlore, (?), is used in swimming pools; S. Thiosulfate.    Dan

i think that my way is easy and cheap:
i buy soft no gas bottled water, it cost me about 1 Euro for a dozen
litres.
CLearly in Italy there is a large amount of kind of bottled water but
every kind of this (evian here is cheap here...).
There is not an absence of minerals like demineralized but a very low
content of minerals. And it's more than enough.
In summer only I use demineralized  water only for the last rinse with
wetting agent.
Believe me it's ok!!

ciao,
Stefano