"To manyworkers, the stop bath is merely a splash of acid in a vague amount of water. It should be compounded as directed." Ansel Adams
Originally Posted by bessa_L_R3a
OTH, I'm sure that several water changes with agitation is equally effective and with minimal to no downstream, er, negatives. If it works, go for it. Remember, the bumblebee can't fly, either.
Kodak SB-6 Stop Bath: Sodium bisulfite 30 g, water to make one liter
Kodak SB-7 Stop Bath: Citric Acid 15 g, water to make 1 liter
The same baths with an "a" suffix are stronger for strong alkali developers. 37.5 grams of citric acid (not 37 or 38? :rolleyes or 75 grams of bisulfite.
Or, bottom line, 1/3 white vinegar, 2/3 water. Take that, Ansel!
All per Kodak.
Not using with paper is not such a good idea, even more so if you are using fiber based papers. I wouldn't worry so much about over development. That's pretty hard to do if you've exposed the paper correctly, since development is carried through to completion. The problems, veiled highlights etc., come about when some of the alkaline developer gets carried across to the acidic fixing bath. That's a sure way to cause staining and possibly some fogging of the highlights. You need to be extra cautious about washing the paper free of developer before its immersion into the fixing bath. That's tough to do in a tray without constantly changing water. The first couple of prints may work out OK, but after that the amount of developer carried over into the stop tray becomes significant enough to be of concern. If you have a sink in your darkroom, then you can use water rinse to your heart's content at the expense of a lot of wasted water. I don't see any advantage to this save the absence of the stop bath odor, which is not so bad if you've diluted your stop bath to the proper strength. It's only acetic acid at half the strength of table vinegar. If the odor of stop bath is bothersome, I'm willing to bet that the working solution is too strong.
Originally Posted by DannL
I use a stop bath with paper but not with film.
I only use a water stop bath with film if I plan on re-using the fixer. If the fixer is going to be discarded after use I just pour out the developer then pour in the fixer.
Why would you discard the fixer after use?
Originally Posted by Steve Smith
tim in san jose
Where ever you are, there you be.
Sorry, I should have been more specific - I said 'If the fixer is going to be discarded". It does not last forever.
Originally Posted by k_jupiter
If I am going to re-use the fix, I will use a water stop, if the fix is at the end of its useful life and is going to be discarded, I don't bother with the stop stage.
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I formally used an acidic stop bath with film but when I started to use staining developers, I went with a water bath. Thereafter, I used a water bath for all film and did not see a difference. However, my results are anecdotal and should be taken in that context.
"The secret to life is to keep your mind full and your bowels empty. Unfortunately, the converse is true for most people."
Originally Posted by k_jupiter
Why would you NOT?
The fixer rapidly accumulates insoluable silver salts, which will eventually precipitate out onto the paper, and (being insoluable) cannot easily be washed away. That is why there are clear guidelines for the use of two fixer baths for archival prints, and why there are limits on how long you can use a finite amount of fixer.
I'm also a big fan of a dilute sodium sulfite bath after the fix, to re-dissolve those little salty buggers before the final archival wash.
I used to be very anti stop bath and still am with film - I have had pin holes that were caused when the ph basic developer engaged the acid stop bath in the emulsion. Does development continue in a water bath? - absolutely - until it is exhausted. I know that exhaustion of developer in the emulsion could take as much as two minutes in a water bath - or longer. Is this important? I don't think so - I usually rinse my film for 2 or more minutes in a water bath before going to the fix. I do NOT use acid fixer - only ammonium thiosulfate based with a ph of about 8. I test my fixer with every use. My fixer TF3, can clear film in 30 seconds. At 45 seconds to one minute of clearing time, I chuck it for fresh. I did not do this in the early years and my legacy work shows it. This is the error that comes back to haunt you in 5 years or so. Keep your chems fresh.
I did go back to using stop bath in paper though. It is not so important with normal paper developers (Like PC-TEA or Dektol) but with Amidol based (staining) developers, I noticed staining when I only used a water stop. I get this stop bath mix from B&H photo - it smells like vanilla. It is inexpensive, it has a traditional indicator in it and I have had no staining issues with Amidol since using it. I also know that my fixer lasts longer and I can switch the lights on a little quicker to examine a print when I use stop bath. I do not know what is in it but it is nothing like acetic acid. - Likely something more like citric acid. I guess there are issues now in shipping acetic acid so traditional stop baths are less available for mail order sales.
I also use a fixer clearing agent - I do not do the two bath fix routine - but I make my first wash one with some sulfite in it.
My photos are always without all that distracting color ...
I use a stop bath, and my reasons are pretty much covered by Bob's post on page one.
I'm not worried so much about the continuation of development while in the water bath. I am however, quite careful with my stop, as I use the (obsolete, yes I know) kodak powder fixer in the nice yellow/orange envelope, and it has limited capacity, and needs to be treated gently. An acid stop allows me to do this, and since I develop with the (yes I know, no imagination) divided D-76, I don't have any problems with pinholes as I might with any of the very exotic developers.
I trust my experimenting will be the cause for my ultimate demise.
Originally Posted by fschifano