wash aid - home brew

[patricia de roeck]

Just done a search on this and the most popular suggestion seems to be 1 teaspoon of sodium sulphite per litre of water - terrific because I've got plenty of it - just a couple of questions though - my tapwater is average ph so do I still need to use distilled water instead - also I realise its one-shot but will it keep for a couple of days in a lidded container or do I have to ditch it when I've finished the printing session?
Thanks everyone. Patricia

 

[lee]

just use regular tap water I been doing this for many years.

lee\c

 

[Ian Grant]

Patricia, Sodium Sulphite is perfect in approx the strength your using, Agfa B&W paper data sheets also recommend sodium carbonate.

I've never used distilled water to wash prints but I do carefully swab to remove all water from the emulsion surface before I dry them, so I don't get drying marks.

Personally I would use a small domestic (de-ionising) water filter system rather than commercial distilled or de-ionised water. These are so cheap and start at around £12/$24US for a jug type used to filter water before using in a kettle, many houses install larger in-line versions to provide drinking water at a kitchen tap.

I've not answered re-use but personally it's not worth it.

Ian

 

[fschifano]

If your tap water is reasonably clean, and most tap water in the US is, there's no need for anything else. Mix up the sulfite as recommended and use it. No wash aid at working strength has a long shelf life, so just chuck it at the end of the session.

 

[Ian Grant]

It is worth bearing in mind that not all tap water is treated/purified. I know from experience as our tap water comes from a borehole, is safe to drink but undrinkable due to high mineral/salt content.

If you get drying marks on your negatives then it is worth rinsing your negatives in distilled or de-ionised water, and if the water is particularly bad your prints as well.

Ian

 

[Lee Shively]

Tap water is fine, IMHO. The only time I use distilled water these days is during the summer when the cold water runs too hot. I keep several gallons of distilled water available in the darkroom to mix up diluted developer, fixer, stop bath, etc., because the water will then be the same temperature as the stock solution.

 

[Richard Wasserman]

I use sodium sulfite in tap water as a wash aid. My understanding though is that 20 grams/liter is the necessary amount, which works out to a scant tablespoon of sulfite not a teaspoon. Does anyone one know if this is correct?

Richard Wasserman

 

[dpurdy]

The formula I have says to add in a pinch of sodium bisulfite, though I don't bother with it. If you use a lot of sodium sulfite, as I do, you can get it a lot cheaper than the photo store or formulary price by going to a regular scientific supply or chemical supply house. I get 50 pounds for 60 dollars. Or maybe it is 60 pounds for 50 dollars. Whatever it lasts a long time.

 

[Lee Shively]

I buy the mentioned sulfites from this place:

http://www.chemistrystore.com/index.html

There may be a cheaper source but the prices here are pretty good compared to photo-designated chemical sources.

 

[BBMOR]

hey

the home brewed washaid with bisulfit or Na carbonate or even salt, normal NaCl kan be used ,never use destilled or softed water for m ,the more salt in the water the better it can be used as a washaid ,seewater is the cheapest if you live close enough

 

[dpurdy]

I buy the mentioned sulfites from this place:

http://www.chemistrystore.com/index.html

There may be a cheaper source but the prices here are pretty good compared to photo-designated chemical sources.

That place is great. thanks. Check the price of sodium carbonate as well.
I will use them next time.
Dennis

 

[schlger]

My reciepe is:
110g Sodiumsulfit
28 Sodiummetabisulfit
5,5g EDTA Tetrasodiumsalt
5,5 Sodiumcitrate

Even with that reciepe in which the EDTA and the citrate serve as complexing agents for keeping the calcium und magnesium ions from tap water in solution, with my iron polluted tap water a white percipate may occur, that could rest as a grayish scum on the prints. So good tap water is fine but in my case I have to use reverse osmosis water.

 

[dancqu]

...,seewater is the cheapest if you live close enough

Soon enough many will be living closer than they care. Dan

 

[removed account4]

hey

the home brewed washaid with bisulfit or Na carbonate or even salt, normal NaCl kan be used ,never use destilled or softed water for m ,the more salt in the water the better it can be used as a washaid ,seewater is the cheapest if you live close enough

using sea water reduces washing times as well.
but then you have to deal with all that plankton .

 

[dancqu]

No wash aid at working strength has a long shelf life,
so just chuck it at the end of the session.

Ian has mentioned Agfa's recommended sodium carbonate.
On a pound for pound basis, IIRC, about 1/4 more equals
sodium sulfite in capacity. S. carbonate though does not
need to be chucked. So compare with S. sulfite which
starts going bad as soon as the lid is off.

I think sulfite is used in a fingers crossed manor. It oxidizes
into the sulfate. With a most minute amount of certain
elements in the water or the sulfite itself it will
experience catalytic accelerated oxidation.

Perhaps that is why Agfa never followed the pack and
for many years recommended sodium carbonate. There is
no ?"how shot is my hca?" from being exposed and stirred
and in and out of the bottle. The only issue with carbonate
is capacity. Agfa's 2% solution strength I'd think would
yield about the same capacity as a sulfite based HCA.
Perhaps Ian can add a few more details of the Agfa
method. Considering the importance of an hca in
reducing time and water needs the use of any
HCA should be better defined. Dan

 

[Ian Grant]

This is from the Agfa Data sheet for Record Rapid:

A soda bath (1 % sodium carbonate solution) can be included for fiber-base paper, between fixer and final wash. This ensures that the fixer is washed off the paper surface faster and more thoroughly. This not only cuts down the final washing time by about 30 %, and in particular it increases the prints' durability. If a hardener-fixer is used, the soda intermediate bath is not recommended.

L F Mason in his book Photographic Processing Chemistry mentions the use of Sodium Carbonate or Sodium Sulphite as a wash aid. Mason was head of research at Ilford.

Ian

 

[dancqu]

[QUOTES=Ian Grant;541001]
"This is from the Agfa Data sheet for Record Rapid:"

"A soda bath (1 % sodium carbonate solution) can be included
for fiber-base paper, between fixer and final wash. This ensures
that the fixer is washed off the paper surface faster and more
thoroughly. This not only cuts down the final washing time by
about 30 %, and in particular it increases the prints' durability.
If a hardener-fixer is used, the soda intermediate bath is
not recommended."

That last sentence likely explains why sulfite is the usual
base of HCAs. It works well and has a lower ph, safer for
fixer-hardened emulsions. With today's pre-hardened
emulsions sulfite's advantage is likely lost. I doubt
Agfa would otherwise suggest carbonate. For
myself a HCA which does age is advantages.

The problem with carbonate is that it's use is not well
spelled out; times, capacity, and ?. Dan

"L F Mason in his book Photographic Processing Chemistry
mentions the use of Sodium Carbonate or Sodium Sulphite
as a wash aid. Mason was head of research at Ilford." Ian

 

[fhovie]

right wrong or indifferent, I have been using a two bath wash. My darkroom has water storage and disposal but not an endless supply for either so I have been putting my prints (fiber or RC) in a 5gal bucket full of water with a few tablespoons of sulfite for about 10 minutes and then in a large sink filled with about 25 gal of fresh water for another 30 minutes or so. I figure the leaching and thiosulfate concentrations will be very very small after this and so I am using this for now.

 

[dancqu]

[QUOTES=dancqu;541904]

"That last sentence likely explains why sulfite is the usual
base of HCAs. It works well and has a lower ph, safer for
fixer-hardened emulsions. With today's pre-hardened
emulsions sulfite's advantage is likely lost. I doubt
Agfa would otherwise suggest carbonate. For
myself a HCA which does age is advantages."

That last sentence should read, ...does NOT age... .
Carbonate that is. It does not oxidize.

"The problem with carbonate is that it's use is not well
spelled out; times, capacity, and ?." Dan

 

[KWhitmore]

LOL

using sea water reduces washing times as well.
but then you have to deal with all that plankton .

Um, what kind of food do they serve at the Chum Bucket other than Krabby patties? That's soooo funny.

 

[removed account4]

Um, what kind of food do they serve at the Chum Bucket other than Krabby patties? That's soooo funny.

mr. p WISHES he was serving krabby patties at the chum bucket,
but he has been unable to swipe that secret recipe.

 

[john_s]

Some info at:

(there was a url link here which no longer exists)