question on water hardness effects

[ampguy]

I haven't processed film in 20 years, and don't plan to soon, but as I'm in the process of analyzing our water hardness and quality, I'm curious what the effects are on photographs with hard water vs soft water, or relatively pure water vs mineral or high TDS water?

OT: we like soft water, and our ion exchange unit works great, but we're concerned about the 8lbs/sodium/week that doesn't get filtered out from our drinking/cooking water.

 

[markinlondon]

I'd be mainly worried about water marks left after the final rinse. We have "well 'ard" water here in London so I make up my photoflo in deionised water for the last stage. Photo chemicals are pretty well buffered so it shouldn't make much difference to other working solutions.

 

[x-ray]

I had a conversation with a Kodak rep about mineral content in water used to mix chemicals. I asked about mixing the chemicals in deionized water or distilled. I knew that deionized water has a slightly different Ph that average tap water. The rep told me do not use deionized or distilled water. He said chemicals are formulated to be mixed in water with an average hadness and mineral content. He also said the change in PH of deionized water was a no no. I would be definately concerned about sofe=tened water and the added sodium content. I should be OK to wash with but not to mix chemicals and particularly developers.

 

[icebear]

pH value might have more visual effect

pH value might have more visual effect

I had a friend working as a pro with Linhof 15x18 and doing his own E6 process on the sheet film with a Jobo rotation machine. He used to test every batch of film and adjusting the pH-value of his chemicals to get the perfectly accurate color. There definately is quite an obvious effect in the sense of cool/warm toning similar to BW toning. I don't have experience in different hardness values, just common sense would tell you that a high mineral content would give you better chances of residue i.e. watermarks.

 

[ampguy]

interesting

interesting

I guess it's good that you don't need distilled water, but it seems like some loose chemistry there since hardness and mineral content varies widely along with solids contents in water, and variable plumbing situations, where with distilled you have a known entity, though bottled is all over the place, though certain brands are consistently close to distilled.

I had a conversation with a Kodak rep about mineral content in water used to mix chemicals. I asked about mixing the chemicals in deionized water or distilled. I knew that deionized water has a slightly different Ph that average tap water. The rep told me do not use deionized or distilled water. He said chemicals are formulated to be mixed in water with an average hadness and mineral content. He also said the change in PH of deionized water was a no no. I would be definately concerned about sofe=tened water and the added sodium content. I should be OK to wash with but not to mix chemicals and particularly developers.

 

[vladhed]

I've just processed my first rolls of B/W (HP5+ in D76) since moving into our new house, which is on a well. The water is very hard, and seems to have a lot of rust (iron) in it. No water softener yet but given the brown-red stain in the soap chamber of our cloths washer it might be time to think of one.

Thankfully B/W development seems to be so forgiving that nothing seems to be any different than the chlorinated tap water I used to use.

Usual dosage of dish-soap to the final rinse seems to take care of any water marks.

I haven't processed film in 20 years, and don't plan to soon, but as I'm in the process of analyzing our water hardness and quality, I'm curious what the effects are on photographs with hard water vs soft water, or relatively pure water vs mineral or high TDS water?

OT: we like soft water, and our ion exchange unit works great, but we're concerned about the 8lbs/sodium/week that doesn't get filtered out from our drinking/cooking water.

8lbs for drinking/cooking! Do you only have soft water going to your taps? Typically less than 5% of your weekly water usage winds up being injested. The bulk of North American water usage is for washing clothes/dishes, flushing toilets and bathing.

 

[ampguy]

good point

good point

You're correct, the 8lbs/week salt usage is for the whole house water use, with only a minute # of grains being consumed, but still a minor concern for us (we're aware of KCl alternatives). Our particular unit needs 7-8lbs min. for resin longevity, and also in auto mode needs to cycle/regen once per week, so we can't tradeoff less sodium for slightly harder water easily.

Yes, you'll probably want to get a good softener that works well with de-iron solutions, and may also want an RO or other water purifying appliance. Be sure to get a TDS meter to monitor your water quality without having to send out lab samples all the time.

I've just processed my first rolls of B/W (HP5+ in D76) since moving into our new house, which is on a well. The water is very hard, and seems to have a lot of rust (iron) in it. No water softener yet but given the brown-red stain in the soap chamber of our cloths washer it might be time to think of one.

Thankfully B/W development seems to be so forgiving that nothing seems to be any different than the chlorinated tap water I used to use.

Usual dosage of dish-soap to the final rinse seems to take care of any water marks.



8lbs for drinking/cooking! Do you only have soft water going to your taps? Typically less than 5% of your weekly water usage winds up being injested. The bulk of North American water usage is for washing clothes/dishes, flushing toilets and bathing.

 

[Xmas]

Drink bottled water, only give junior bottled water.

For photo unless colour or mixing own powder chems only thing to do is final bath rinse in deminiralised, + photo detergent, + clean squegee.

I moved to soft water area, descaled the kettle on moving in years ago, still looks ok.

Noel

P.S. only use the low sodium sub in cooking on table.

 

[ampguy]

what's a "sub" ?

 

[Xmas]

sub = substitute

In the UK you can buy a table salt which is lower in NaCl, i.e. has more KCl. Some people are on low salt diets, after heart or other med problems.

Noel

 

[Trius]

x-ray et al, very interesting and I can't comment on colour processing, but I use water from my dehumidifier (which I then run through Brita filtration) for all my b&w processing. I don't see any adverse affect, though I do know it's not the same as commercially distilled or deionized water.

Yes, it may mean my times are adjusted to compensate, but I don't see that, either. For example, my TX @200 in Rodinal 1:100/20C for 20 min. is straight from either the MDC or the Agfa (RIP) insert (can't recall right now), and it seems spot on.

But some other questions about the "formulated for average tap water hardness" statement ... what is average? What should the photographer who processes out in the boonies do compared to the guy on NYC water? Water can vary one city/town/village away. I don't know what type of "Kodak rep" gave you the info, but if it's a sales rep, well then...

I do think that for developers with high sulfite or other solvent action there could be a big difference that buffering may or may not be able to accommodate. But I'm not a chemist... it was my minor in university but that was a generation plus ago. Photo Engineer over on APUG might be a good source of info on this subject.

Bottom line is, for serious work, careful testing, calibration and control is required. This is why Kodak, Fuji, etc. can provide lots of information and control strips for professional labs and professionally-oriented darkroom workers.

 

[ampguy]

ahh ok

ahh ok

yes, we have that here as well for table use, but I got confused, because we also have both for water softeners as well, though the KCl is much less popular and costs about 3-4x that of the sodium based softening salts.

sub = substitute

In the UK you can buy a table salt which is lower in NaCl, i.e. has more KCl. Some people are on low salt diets, after heart or other med problems.

Noel

 

[kaiyen]

I had some serious issues with hard water in my previous place of residence, and had to switch to distilled for the final rinse and photo-flo. That solved it.

The only things I've heard, and they are not definitive (certainly no quotes from Kodak), is that slightly hard water is okay, but soft water and definitely _softened_ water is bad. The added minerals to soften the water can have bad effects in terms of wash, archival qualities, etc.

My water in my current place is oxygenated like crazy. It actually looks like it's boiling when I pour a beaker from the tap into my processing bucket (I make up a bucket at 68F for processing,r ather than trying to figure out the magic spot where my tap comes out at that temperature). But after the air gets out, and with the use of distilled at those aforementioned steps, I've had no issues at all with drying marks.

allan

 

[ampguy]

actually

actually

"softened" water reduces the minerals Calcium and Magnesium, during an ion exchange process, and replaces them with salt molecules, usually sodium or potassium, so softened water has less minerals than hard water, but more than distilled.

Soft water, whether natural, or processed is usually defined as being around or below 50 ppm or 3 gpg (grains per gallon), with very hard being somewhere north of 250 ppm (15 gpg).

You can get free test strips from a Lowes, and probably HD. The city/municipal water reports won't be too helpful since house and neighborhood plumbing have a large effect.

I had some serious issues with hard water in my previous place of residence, and had to switch to distilled for the final rinse and photo-flo. That solved it.

The only things I've heard, and they are not definitive (certainly no quotes from Kodak), is that slightly hard water is okay, but soft water and definitely _softened_ water is bad. The added minerals to soften the water can have bad effects in terms of wash, archival qualities, etc.

My water in my current place is oxygenated like crazy. It actually looks like it's boiling when I pour a beaker from the tap into my processing bucket (I make up a bucket at 68F for processing,r ather than trying to figure out the magic spot where my tap comes out at that temperature). But after the air gets out, and with the use of distilled at those aforementioned steps, I've had no issues at all with drying marks.

allan