Stop Bath Chemical

<p>I make use of plain water for stop bath.......heard acetic acid helps......please suggest how to make a stop bath chemical at home.....and how to use it</p>

<p>Right here http://www.photo.net/black-and-white-photo-film-processing-forum/00Z2C7</p>

<p>Pour out the developer, add enough stop bath solution to cover the film, agitate for 30 seconds, pour out and add fixer.</p>

<p> </p>

<p>You can always use white vinegar. Do a search here for the dilution.</p>

<p>Or you can use one of the "<a href="http://stores.photoformulary.com/-strse-148/TF-dsh-4-Archval-Fixer%2C-Swan/Detail.bok">Archival Fixers</a>" from Photographers' Formulary that is chemically balanced so that no stop bath is needed, just a quick rinse with water and then fix. It is made originally for print paper, but it works equally well with most modern films.</p>

<p>You can use white vinegar available from many grocery shops. It usually comes in 8% or 10% strength. I dilute this 1 part vinegar + 9 parts water. That gives more or less a 1% working solution. The generally accepted working strength is 2% and then you can reuse the solution. I do not reuse, and then 1% works fine.</p>

<p>You can also use citric acid in powder form. This you can find in the cleaning department of many supermarkets. Use one table spoon in one liter of water. Dissolves easily.</p>

<p>Or use plain water.</p>

<p>I think the 1 part white vinegar+ 9 parts water sounds simple.........hw long shud the film be put into stop bath?? can it be directly put into the fixer after the water+vinegar stop bath??(I asked this just to be absolutely sure...and don't want to end up loosing a film with precious moments shot)</p>

<p>Here is one for you, acetic acid is also in Orange Juice, buy yourself some pulp free orange juice and try that out for your stop bath. I usually use Kodak stop bath diluted in one gallon. I stop bath for 30 seconds. I have been successful using orange juice for 3 minutes when I was out of Kodak stop bath once.</p>

<p>be very cautions if you find Glacial acetic acifd 28%<br>

it is quite strong and can harm you if you get it on your skin<br>

I think it has a poison label<br>

if you have children in the home do not even buy it<br>

and NEVER put a photo chenical in a bottle that was used to hold food or drink.<br>

Plastic soda bottles are cheap and handy<br>

BUT this will encourage children to "take a sip"</p>

Distilled white vinegar is 5% acid. Not 10%.

 

I don't think your actually diluting it to .5% is at all harmful.

 

For one can use water as a stop bath.

 

 

Using orange juice seems either like a prank or a waste of money to me. Distilled white vinegar has no contaminants,

pure, and cheaper. But what do I know, film was once made with egg whites, and now made with rendered horse and

cow bones.

<p>Depending on what country you live in white vinegar ranges from 5% to 10%, or higher. The percentage is always on the label, strength and production methods are usually regulated by the food laws in a country.</p>

<p> Stop bath is usually 1-2% so if you have 5% vinegar, dilute 1 part vinegar with 2 to 4 parts water. 30 seconds in the stop bath is long enough to neutralize the developer.</p>

<p>Glacial acetic acid is around 99% or better pure and crystallizes at 16C or so. Acetic acid is sold in a 28% dilution, it is not glacial acetic acid. Kodak indicator stop bath concentrate is around 95%. Glacial looks just like a bottle of water, treat it with respect, it, 28% and Kodak's concentrate can all be dangerous to your health.</p>

<p> </p>

<p>You can use for a stop bath 1,5% - 2% Acetic Acid. But it smells and making it from a concentrated solution >30% is not without any risk.</p>

<p>You can also use Citric Acid (here available in the super market too), 1,5% which means 15g/liter. Almost odorless, a little bit lower in pH but more pleasant to work with. Dump it together when your fixer is exhausted.</p>

<p>Best regards,</p>

<p>Robert</p>

 

<p>Stop Bath, 2% to 6% acetic acid (or just a nice darkroom smell is what I often use). I have either 28% or 99% acetic acid in a liquid detergent squeeze bottle, give it a squirt in a tray or tank of water until I like the smell. How's that for science, but don't let the kids get around it.<br>

Lynn</p>

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Stop bath is one of those nonessentials: Developers work only in a alkaline environment. We move film or paper to a stop bath which is an acid environment. The idea is to counteract the developer thus stopping this action. The ideal stop bath contains a prescriptive which is sodium sulfate. Thus a typical formula would be 500ml acetic acid --- 45 grams sodium sulfate – water to make 1 liter.

 

 

The acetic acid does the trick; the sodium sulfate reacts and rescinds staining agents (spent developer). This formula also prolongs the life of the next chemical which is the fixer. These two stop bath ingredients are also constituents of the fixer. Thus carry-over riding piggyback on film or paper is reduced in its influence to dilute the fixer.

 

 

In a home darkroom setting, with minimal work load, you can use plain water as the stop bath. This works but not a quickly as an acid solution. Likely you will not see any significant difference. Since film and paper emulsions are sponge like, it that they absorb and hold fluids, plain water is not as effective as an acid bath when it comes to prolonging the life of the fixer.

 

 

That being said, table grade vinegar is commonly 3 to 5% acetic acid. A 3% solution of vinegar will do this trick. Read the vinegar label, dilute to 3%, you have made a satisfactory stop bath.

<p>Here is one for you, acetic acid is also in Orange Juice, buy yourself some pulp free orange juice and try that out for your stop bath. I usually use Kodak stop bath diluted in one gallon. I stop bath for 30 seconds. I have been successful using orange juice for 3 minutes when I was out of Kodak stop bath once.</p>

 

Sorry, this is nonsense. There is no acetic acid in orange juice; it contains a small amount of citric acid. It also contains fructose, colouring and other sticky substances that you don't want on film or paper.

 

Just use white vinegar or citric acid powder. Citric acid powder is commonly sold very cheaply as kettle descaler. About one rounded teaspoonful to a pint of water - 5g to 500ml of water - of citric acid powder will give a serviceable stop bath.

 

Almost any weakly acid solution will do as a stop bath. Boric acid, or sodium or potassium metabisulphite can also be used.

Edited June 16, 2018 by rodeo_joe|1

I can only tell you what i have been doing for years in my home darkroom.

 

Black and White film in your typical Plastic/Steel Tanks....i use Straight Water. Never saw the need for anything "more".

 

For paper, in trays, i use Citric Acid. The exact amount is not critical IMO. Those plastic spoons you get, from a Fast-Food "Restaurant" .....one spoonful to One Liter of water. It is SO Easy and SO Cheap, i change it every day.

 

The trouble with straight water for paper is...it QUICKLY becomes very dilute developer.

good luck

Water as a stop is fine, although keep in mind an acid stop bath prolongs fixer life by maintaining its acidity.

Water as a stop is fine, although keep in mind an acid stop bath prolongs fixer life by maintaining its acidity.

Yeah, excellent point.!

And again, Citric Acid is so affordable, sometimes i change it a few times during the day (somebody on my second enlarger for several hours) so the fix does not get polluted.

Frankly, a bottle of a dedicated stop bath (like Ilfostop or Fomastop) costs very little too, and lasts very long. I'm sure the alternatives work as well, but when using a normal developer, I see little reason to take any risk. The savings are nowhere near enough to make it worth it to me.

Diafine recommends only water instead of acid stop bath.

 

For one, it isn't time sensitive, but I suspect that part B has

a lot of carbonate in it, maybe more than most developers.

 

It looks like D-19 has 52.5g/L, but many don't have any carbonate.

 

I suspect that means that fixer won't last as long as it would otherwise.

Diafine B is close to pH=13 so very alkaline. In theory you can get bubbles on the film surface when changing to a strong acid stop bath. The only reason it is not recommended.

http://fotohuisrovo.nl/documentatie/Diafine-data.pdf

 

Here is the Diafine data.

Diafine B is close to pH=13 so very alkaline. In theory you can get bubbles on the film surface when changing to a strong acid stop bath. The only reason it is not recommended.

 

That is what I always suspected, but didn't know for sure.