Vinegar stop bath

[Claire Senft]

Claire Senft submitted a new resource:

(there was a url link here which no longer exists) - Vinegar stop bath

This is a safe and effective stop bath that is quite inexpensive. It will not indicate exhaustion. If left too long in a tray it might form mold. Go to the store and buy the cheapest vinegar available. Mix 1 part Vinegar with 4 parts water.

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

 

[don sigl]

Indicator stop baths are really unecessary. You can tell if a stop is active by rubbing the liquid between your fingers. If has a greasy feel, it is alkaline. I was told this by a professor way back when I was a lowly freshman. Initially, i didn'rt believe him. Sure enough, as the acidity wears off, the liquid will begin to feel greasy. I've been using this method to monitor stop bath ever since.

 

[Blighty]

Daft as this may sound, does it matter which type of vinegar you use. Should I use ordinary malt vinegar or the colourless distilled variety? Cheers, Blights

 

[Justin Cormack]

I would just see if it stains the paper at all - stop a test strip for an extra long time. If its a bit browny after washing get some clear vinegar.

Lots of people seem to stop in water in places with acidic water.

I have a digital pH meter (not expensive), so indicator isnt any use, though its hard to get no indicator stop anyway. Now I have strted buying raw chemicals for alt process etc I am finding I have ingredients to make stop etc anyway.

 

[Petzi]

I would not use vinegar for my photos.
Acetic acid costs next to nothing, and vinegar is not pure.

 

[paradoxbox]

sorry to bump an old thread but i came across this while looking around about stop baths - vinegar works fine as a stop bath. you can make your own "acetic acid" by boiling off the water content in regular vinegar. it's the same thing.

incidentally if you want a cool party trick, try boiling down vinegar in a glass pot until it starts to froth at the edges. take it off the heat and let it cool to room temperature. then flick a drop of water into it and watch as it turns into "ice". pretty neat trick.

 

[Sirius Glass]

The cost of stop bath with or without indicator is so low, why bother? Hypo on the other hand can be expensive, but guess what? My photography is important to me, so I will pay the freight.

Steve

 

[maciekz]

The cost of vinegar is even lower, and it is easier to obtain. The best effect is with 2% concentraition of acetic acid in water, as claimed by literature. And food-grade commonly sold everywhere is simply acetic acid and water - I've chced it with many brands.
And using a not working stop bath is usually not dangerous and would be noticed very fast if you do monitor the fixer. For stoping film development it is no risk, because it is so cheap that there should be no problem with using it one-shot.

 

[Sirius Glass]

But why risk contaminants?

Steve

 

[eclarke]

Buy Heinz white vinegar, they have been making vinegar since 1869. I'm pretty sure it's pure..EC

 

[maciekz]

I have actually chcecked many times they are pure. Anyway you can buy pure acetic acid from a reputable chemical company (with analytical certificate, which isn't usally available on stoch photo stop baths). Here where I live this tends to be roughly 10% more expensive, and not everyone has a chemistry dealer around the corner.

 

[Sirius Glass]

maciekz is talking about reagent grade chemistry which is much better than supermarket grade chemistry. If you can get reagent grade chemistry and are comfortable with it, then use it.

Steve