stop bath

terri

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I'm trying to line up all my chemical purchases for the darkroom. In perusing stop baths, I saw that Ilford makes one called "Ilfostop" which is advertised as "a low odor citric acid" stop bath, claiming to be "specifically recommended for dish/tray paper processing or tank professing of film". Doesn't seem to have any acetic acid in it, which means it can be shipped directly to me, as opposed to all the standard 28% acetic acid stop baths which have to be purchased in-store.

Anybody ever used this Ilford stuff (or one like it)? I'm curious about its performance.
 
If you're concerned about the shipping of a stop bath (HAZMAT thing) then just use vinegar and water.
 
Thanks for the info, Hertz.... :D

Well, common household vinegar is (I think) only 5% acetic acid, don't know if it would be much use in the darkroom....? The regular stop baths seem to carry a 28% solution, hence the hazmat designation.

Actually, we had a highway shut down in the last 2 weeks for what was called a "chemical spill"....people being evacuated and all that. Turns out it was acetic acid....the air indeed had a vinegar-like smell. Gee, wonder if they dumped stop bath all over the highway??? :lol:

I can go purchase regular here, just wanted to save myself a trip - and was curious about this other stuff which seemed to be safe to transport.
 
Yes but you dilute stop down quite a lot so you actually use it at only 1 or 2%. You just dilute vinegar less. Instead of 1:30 use something like 1:6 or even 1:12.Don't use malt vinegar - use the white spirit vinegar. And it works better if you add 5% Potassium metabisulphate as a buffer. But then you might as well buy the real thing. ;-)
 
I use Ilfostop at home but its the only stop bath i've ever used so I cant tell you if its good. At school we dont use a stop bath we just rinse the film under running water for 1 minute or rinse the photo in just a tray of water for 30 secs which seems to work.
 
i bought kodak stop bath at a camera store and it was actually cheaper than online.

Try a store so you dont have to worry about paying extra.
 
will965 said:
I use Ilfostop at home but its the only stop bath i've ever used so I cant tell you if its good. At school we dont use a stop bath we just rinse the film under running water for 1 minute or rinse the photo in just a tray of water for 30 secs which seems to work.

mmmm, plain water I've not tried, I've only used regular stop. And I've not prepared it myself so am unfamiliar with the dilution factor, too. "malt vinegar"....? sounds smelly!! I use plain old distilled white vinegar, around the house and also for some alternative processes, but wouldn't have thought to dilute it for a stop bath!

Thanks for that bit of info, Will. :D I'll probably end up making the drive to the photography store that sells the regular stuff - just end up paying more.
 
Running water doesn't actually stop development - it just dilutes and chills the chemicals and slows things down a bit. It can give you unevenly developed patches and I wouldn't advise it - certainly not for archival prints.
Malt vinegar is made from beer and is a brown murky thing. We Brits use gallons of it - especially on chips. It is rather pungent.....
 
Hertz van Rental said:
Running water doesn't actually stop development - it just dilutes and chills the chemicals and slows things down a bit. It can give you unevenly developed patches and I wouldn't advise it - certainly not for archival prints.
Malt vinegar is made from beer and is a brown murky thing. We Brits use gallons of it - especially on chips. It is rather pungent.....

True it doesnt stop it but it does wash off the developer, unless the film absorbs the chemicals but i dont know.
 
will965 said:
Hertz van Rental said:
Running water doesn't actually stop development - it just dilutes and chills the chemicals and slows things down a bit. It can give you unevenly developed patches and I wouldn't advise it - certainly not for archival prints.
Malt vinegar is made from beer and is a brown murky thing. We Brits use gallons of it - especially on chips. It is rather pungent.....

True it doesnt stop it but it does wash off the developer, unless the film absorbs the chemicals but i dont know.

Yes, it does. The emulsion has a gelatine base and it absorbs just about everything. As I said, development continues to take place but at a slower rate. This is because of the chemicals within the emulsion. Washing under the tap will not remove the chemicals evenly at a fast enough rate to stop uneven development. Acidifying the water changes the pH balance which stops development virtualy instantaneously. :wink:
 
terri said:
Well, common household vinegar is (I think) only 5% acetic acid, don't know if it would be much use in the darkroom....? The regular stop baths seem to carry a 28% solution, hence the hazmat designation.

It's 28% as a concentrated solution, but when you water it down to make a working solution I think the manufacturers usually recommend something around 4%, although I usually mix it a bit weaker than that.

The crazy thing is that as cheap as white vinegar is, stop is actually cheaper (although that may not take into account shipping and hazmat charges).
 
Hertz van Rental said:
will965 said:
Hertz van Rental said:
Running water doesn't actually stop development - it just dilutes and chills the chemicals and slows things down a bit. It can give you unevenly developed patches and I wouldn't advise it - certainly not for archival prints.
Malt vinegar is made from beer and is a brown murky thing. We Brits use gallons of it - especially on chips. It is rather pungent.....

True it doesnt stop it but it does wash off the developer, unless the film absorbs the chemicals but i dont know.

Yes, it does. The emulsion has a gelatine base and it absorbs just about everything. As I said, development continues to take place but at a slower rate. This is because of the chemicals within the emulsion. Washing under the tap will not remove the chemicals evenly at a fast enough rate to stop uneven development. Acidifying the water changes the pH balance which stops development virtualy instantaneously. :wink:

Usefull to know, thatnks :thumbsup: , I'l always use the stop bath now. Does the stop bath affect the fixer, so after the films been in the stop bath and i pour that out and pour in the fixer, will it neutralise the fixer aswell? (Not sure if thats the right wording)
 
ksmattfish said:
terri said:
Well, common household vinegar is (I think) only 5% acetic acid, don't know if it would be much use in the darkroom....? The regular stop baths seem to carry a 28% solution, hence the hazmat designation.

It's 28% as a concentrated solution, but when you water it down to make a working solution I think the manufacturers usually recommend something around 4%, although I usually mix it a bit weaker than that.

The crazy thing is that as cheap as white vinegar is, stop is actually cheaper (although that may not take into account shipping and hazmat charges).

Enough about that...where the hell ya BEEN??!!? :cheer:
 
will965 said:
Does the stop bath affect the fixer

Stop bath helps keep the fixer fresh by neutralizing the developer. Developer kills fixer. That's the main reason I use it. Personally I'm not as concerned about stopping development as much as I am about increasing the longevity of my fixer.

Although there are folks who say stop bath can be harmful to the emulsion. Not to long ago Motcon posted information explaining this. As usual, there is no one right way to do it. There are some "masters" who say always use stop, and others who say never use it. You have to weigh the info and come to your own conclusions.

I like to use a weaker than normal stop bath. Mixed at manufacturer recommended strengths I sometimes have problems with pinholes in the emulsion of 120 and 4x5 film.
 

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