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josh_560
3-Mar-1999, 15:21
I have heard that using stop bath when processing film can cause pinholes in the film. Does anyone know if this is true? What are the disadvantages of using plain water? I never used stop bath when I processed my 3 5mm but I did give up that format because of my continued disappoint with the qu ality. As always any response helpful. Josh Simpson

Blake
3-Mar-1999, 15:52
Never, i repeat, never use stop bath with film and you don't really need any with paper either, IHOP(International House of Pancakes). The disadvantages of tap water are regional. I think you need a basic black and white course before you start jumping formats. Read "Using the View Camera" by Steve Simmons there is one on Ebay right now. I get a strange feeling you're gonna be dissapointed with the quality of your large format too, at first, anyway, keep at it Josh. All you need is one goodun' once in a while to keep you going. Happy Hunting.

Richard Fish
3-Mar-1999, 22:02
Josh, I've used stop bath for 40 years without pinholes. It increases the life of your fixer. Now remember, I've got 3.5 gal tanks of film chemistry going all the time, this is my job as well as my hobby, so keeping everything fresh and workable is important to me. It's true that you don't really need it for either film or prints, but it works fine for me. Dick Fish Smith College

Michael Kadillak
3-Mar-1999, 23:24
Pardon me if I have never heard of pinholes in film from stop bath. I have used stop bath for 15 years without a hitch for both roll and sheet film. To create this on film, I would think that you would have to have uneven and high acidic concentrations to eat away part of the film. But I am not a chemist.

At normal working concentrations, I do not see how this could take place.

John Hicks
4-Mar-1999, 01:16
The use of stop bath with old non-hardened emulsions and high-carbonate develope rs could case pinholes, but I think it's time to lay this one to rest. If you use a stop bath then of course development will stop sooner than it wou ld with just a water rinse, but not instantly, and it can make your fixer last l onger, but let's not be penny-wise and pound-foolish. Pushing fixer to the edge of exhaustion is just dumb. So...it's up to you whether or not to use stop. If you use stop I'll bet you n ever get pinholes...otoh if you don't use stop I'll bet you never have a problem with that either. NOTE: stop bath shouldn't be used with some developers but they're not run-of- the-mill D-76 types and it'll be clearly stated in the docs.

Lot Wouda
4-Mar-1999, 04:19
Would be a tremendous discovery after more than hundred years of chemical photography that stop bath causes pinholes. Just think about the consequences of such a discovery! I like the developer to stop immediately, for reasons of repeatibility and comparability.

Charles Matter
4-Mar-1999, 09:22
Pinholes are (95% of the time) caused by air bubbles lodged on the film. The point of contact prevents chemistry from working there...i.e. the emulsion in that little undeveloped dot will completely dissolve away in the fixing bath, leaving a "pinhole". The problem is agitation (or perhaps airation from your faucet) in the water. Are you tray developing your sheet film..or using hangers???. Are you using a plain water pre-soak prior to development??? Stop bath is a crucial part of the development process as it instantly stops the action of the developer (to allow as precise control of development as possible). It also changes the ph of the film to acetic. This not only prolongs the life of the fixer..it also enables the fixer to work more completely and helps eliminate the possibility of later staining from incomplete or uneven fixing.

Blake
4-Mar-1999, 11:41
Cmatter, do you see a difference in your stopped and unstopped films and papers? Big yellow got ya I think.

james mickelson
5-Mar-1999, 05:48
Overly strong stop bath can cause pin holes. Be sure you are diluting it to the correct concentration. And it doesn't stop developement immediately. It neutralizes the developer film that is hanging on the outside of the film. The emulsion contains developer that is still active but only on the very thin parts of the negative. That's right out of old camera and darkroom techniques a few years back. And yes tribby. I do see a difference in my prints using just plain water. As always.....

Blake
5-Mar-1999, 16:57
Oh come on jack, what difference and how, what if you used ethyl? (that's unleaded for you youngins') Now I know you don't have a densiwhatchacallit. So you might want to clean your spectacles, grampaw. The difference in densities for a second of dev. time? could it be a little muck on your loupe. peeaaaayycccch schmeeeeaaayyyych.

Lot Wouda
7-Mar-1999, 04:16
Pinholes caused by airbubbles are not completely white, they've got a black outer ring. This could be a relevant question in determining the cause of your pinholes.

Geoffrey Bryant
26-May-2000, 07:01
If developer contains sodium carbonate, a strong acid stop bath will produce carbon dioxide, also pin holes. Use plain water rinse, then acid stop to preserve fixer.

Paul Schilliger
28-May-2000, 06:13
I used to keep the older fixing bath as a rinse/stop bath. For paper though, I n oticed that using a stop bath helped keep clean whites.