28% acetic acid?

**Kirk Keyes** · 21-Jul-2009, 16:29

The Energizer Bunny has alkaline batteries, making the contents of them caustic. And corrosive.

**Jim Rice** · 22-Jul-2009, 09:39

Not wishing to interfere with the p****** contest here, but I am curious. Why do folks avoid Kodak's indicator stop? It's the only thing available off the shelf here and there's a finite amount of energy I'm willing to devote to stop bath unless I'm missing something.

**Kirk Keyes** · 22-Jul-2009, 10:02

I use Kodak Indicator Stop. I also have a bottle of 28% acetic. I use them for making a pH buffered stop bath along with sodium acetate, as described in the Film Developing Cookbook by Anchell and Troop. The advantage of a pH buffered stop bath is it can have high acidity but not a low pH. This allows it to stop development very quickly, it lasts a long time, and it reduces the amount of gelatin swell while the film is in the stop bath.

For papers, I got tired of the smell of acetic acid in the open trays, so I use citric acid stop.

**tgtaylor** · 22-Jul-2009, 10:44

It's not necessary to use an acid stop bath for film. In fact, a water stop is probably recommended more often than a acid stop. Agitate for 30 seconds before discarding and adding the fix is the way I learned.

I was using an acid stop for B&W paper but after switching to Photographer's Formulary TR-4 fix, I now use a water stop for B&W paper as well with frequest changes of water. Note, however, that according to the label a stop with TF-4 is not necessary: You can go from the developer directly to the fix.

I now use an acid stop only for C-41 film and RA-4 paper processing in a Jobo processor.

**Kirk Keyes** · 22-Jul-2009, 13:16

There's a lot of things that aren't "necessary", but are still useful.

I prefer to use stop baths as they do have benefits, like stopping development, whereas water "stop" just slows down development via dilution...

But to each his own.

**percepts** · 22-Jul-2009, 13:23

Originally Posted by Jim Rice

Not wishing to interfere with the p****** contest here, but I am curious. Why do folks avoid Kodak's indicator stop? It's the only thing available off the shelf here and there's a finite amount of energy I'm willing to devote to stop bath unless I'm missing something.

acetic acid is dirt cheap if bought in the correct form. Don't get paranoid about indicator stop not being any good. It will work fine but at a stupid price.

**tgtaylor** · 22-Jul-2009, 18:35

Originally Posted by Kirk Keyes

I prefer to use stop baths as they do have benefits, like stopping development, whereas water "stop" just slows down development via dilution...

But to each his own.

True. That's why I use a stop bath when processing color with the Jobo. For example, an 8x10 print in the Jobo requires just 61ml of chemistry - too small an amount to not use an acid stop. Before switching to the Photographer's Formulary Fix I used Kodak Indicator stop bath for B&W paper printing but have always used water for film. But now that it has been brought up and since I have an empty and unused 1/2 gallon container, I'll mix up a stop bath of 1.53% Glacial for film and see if there is any noticable difference.