Fresh Water / White Vinegar sub for Stop Bath?

[css9450]

For those who do stand developing, isn't a stop bath more or less unnecessary (since the developer is depleted)? I could see a plain water rinse in lieu of a chemical stop bath being sufficient.

Correct me if I am wrong.

 

[Highway 61]

I have a degree in chemistry and "white" vinegar is synthesized from high sulfur coal and is used for cleaning purposes. It could be used with food but other vinegars like cider vinegar are used more often because of flavor.

White vinegar is fine.

This is all true. 1+3 diluted white vinegar is just the perfect stop bath. There has been a trend recently advising to use tap water instead of stop bath. It works - but the fixer will then be contaminated with developer and will get exhausted more quickly. Also, while you are using a "stop bath" made of water only, the developer still goes on. Not critical with compensating routine developers, might be critical with some others (what poster #19 wrote, exactly).

White vinegar costs less than $1 a liter at any corner grocery, worldwide. Why some people advise not to use it, nor to use any acid stop bath at all, this I don't know.

Basically you can re-use the stop bath made of diluted white vinegar until the AA smell has vanished and/or until you see some solid deposits (first thing to happen) in your inactinic glass bottle. That is, dozens of rolls.

 

[Rob-F]

I use Kodak stop bath. I don't think the use of plain water will save any time. One 30 to 60 second dunk in indicator stop bath is faster than two one-minute-long water baths.

 

[Highway 61]

Using any branded stop bath instead of white vinegar is just a waste of money. You're using the same stuff, but you pay more for it.

 

[Godfrey]

AFAIK, the main advantage of using a stop bath is longer fixer life (not with all fixers though). ...

Yes. If you use your chemistry one-shot like I do, just use a one minute water rinse for film.

G

 

[Mark Wood]

Are you sure ?? Check your facts:
https://en.wikipedia.org/wiki/Permanganate

Certainly this works, based on the statements of a number of experienced people. But the so-called water-bath method (Saint Ansel, The Negative, 5th edition, Morgan & Morgan, Illustrations 30, 31, 32), for compensating development, seems to imply that the developer in the emulsion continues to act in the waterbath? What to make of that?

Permanganate can't be used as an indicator of pH, which is all the indicator in the stop bath is. From the materials safety data sheet (MSDS), Kodak use bromphenol purple:

https://www.tedpella.com/msds_html/26956 msds mfg kodak stop bath.pdf

Here there's a description of the colour changes that goes through at different pH values:

http://www.sigmaaldrich.com/catalog/product/sial/114375?lang=en&region=GB

For colour changes with permanganate, we're really dealing with reduction/oxidation processes and chemically, that's not what you want a stop bath to do.

 

[Bill Clark]

Correct me if I'm wrong, but I believe this is the chemical used for indicator stop bath to visually determine ph:

https://en.m.wikipedia.org/wiki/Bromocresol_purple

Information on indicator stop bath, material safety data sheet:

http://westliberty.edu/health-and-safety/files/2012/08/KODAK-Indicator-Stop-Bath.pdf

Years ago, I used a product called glacial acetic acid. One whiff of the stock and eyes would water and it about took my breath away! I looked up, and from my research, it looks like indicator stop bath was inventd in 1945 or thereabouts. From what I remember, glacial acetic acid must of been less expensive, hence it's why I used it since I had very little money back then.

Last bit if info:

http://www.tpub.com/photography1/ph209186.htm

Ilford Rapid Fixer which is what I use:

http://www.ilfordphoto.com/products/product.asp?n=45

 

[mbisc]

It depends on what your tap water is like -- in general, the acidic stop bath will stop and neutralize the alkaline developer and thereby extend the lifetime of your acidic fixer. If your tap water is acidic and/or you use fixer one-shot, you may not need stop bath. On the other hand if your city suddenly changes the composition of your tap water and it is suddenly alkaline, you are hosed.

I personally have always used indicator stop bath (mixed with distilled water). I mix it once in 3 months. I $5 bottle of your favor brand will last years. With the price of a single sheet of 4x5 film being $2, I don't know why people want to skimp on the price of stop bath :/

 

[Roger Hicks]

It depends on what your tap water is like -- in general, the acidic stop bath will stop and neutralize the alkaline developer and thereby extend the lifetime of your acidic fixer. If your tap water is acidic and/or you use fixer one-shot, you may not need stop bath. On the other hand if your city suddenly changes the composition of your tap water and it is suddenly alkaline, you are hosed.

I personally have always used indicator stop bath (mixed with distilled water). I mix it once in 3 months. I $5 bottle of your favor brand will last years. With the price of a single sheet of 4x5 film being $2, I don't know why people want to skimp on the price of stop bath :/

Seconded, though I might go for once a month instead of once every three months. The cost really is pretty trivial.

Cheers,

R.

 

[Phil_F_NM]

I've been using water as a stop since 2003 and have no problem. I love my results. One thing has gotten better recently though. I make sure my developer, stop wash, fixer and rinse are all the same temperature or within a degree of the previous bath. That is a big deal for consistency at the grain level and washing a swollen emulsion in much colder tap water can cause some contraction and can also slightly reduce the efficacy of the fixer at the beginning of that cycle.

Phil Forrest

 

[brbo]

I continue to be TOTALLY amazed by my fixer "performance". I don't shoot much BW film (maybe 20 rolls a year) but I mix 1L of fixer (Kodak TMax) and I use that for a year.

I don't use stop, just 1 min of water rinse.

And then we have people that use fixer single-shot. What am I missing?

 

[pepeguitarra]

I would think that regular tap water pH is about 7.4. If the developer is alkaline, let's say pH 8 or 9. Water would be more acid than the developer and could easily stop performance of the developer. So, water itself would be an acid.

 

[ChrisPlatt]

Water stop for film in a daylight tank;
Indicator stop bath for prints in a tray

Chris

 

[roscoetuff]

Thanks to one and all. These Forums are a testament to everyone's good will, as well as to a bit of the telephone game. Typically I'm not able to be specific from the get-go until you guys prod and poke a little. Thanks for that, too, and for your patience.

 

[x-ray]

Are you sure ?? Check your facts:
https://en.wikipedia.org/wiki/Permanganate

I'm certain.

As to using acid stop with TF4 or 5, don't do it. Both fixers are alkaline and depend on their alkalinity to keep the fixer active. Using acid stop will neutralize the fix and drastically shorten its life. One quick rinse in water is all you need.

 

[michaelwj]

The point of the acidic stop bath is to neutralise the developer AND stop the development.

Substituting for water will have a few effects;

1. Development will not stop, but continue at a reduced rate until the fixer applied
2. The fixer will get contaminated with developer and as a result will not last as long
3. You will still have to rinse it with water

#1 won't make a difference unless you're using very short development times
#2 won't matter if you don't want to reuse your fixer too much
#3 means there is no time saving

Personally, I use a stop bath (Kodak indicator), I mix it up and use it for 30 rolls - stored in the fridge in a compressible bottle. I reuse my fixer (Foma) for 15 rolls. Never had a problem with either and my small bottle of stop bath has done about 300 rolls by now - less than 1c a roll.
I'm with Chris and Roger, why bother mess with it?

 

[x-ray]

The point of the acidic stop bath is to neutralise the developer AND stop the development.

Substituting for water will have a few effects;

1. Development will not stop, but continue at a reduced rate until the fixer applied
2. The fixer will get contaminated with developer and as a result will not last as long
3. You will still have to rinse it with water

#1 won't make a difference unless you're using very short development times
#2 won't matter if you don't want to reuse your fixer too much
#3 means there is no time saving

Personally, I use a stop bath (Kodak indicator), I mix it up and use it for 30 rolls - stored in the fridge in a compressible bottle. I reuse my fixer (Foma) for 15 rolls. Never had a problem with either and my small bottle of stop bath has done about 300 rolls by now - less than 1c a roll.
I'm with Chris and Roger, why bother mess with it?

The OP said in post #9 that he's using Formulary TF5. TF5 is alkaline unlike most fixers that are acid. Using an acid stop neutralized and ruins TF5. Formulary clearly states DO NOT use acid stop, it will ruin your fixer. Kodak fixers are fine with acid stop and I'm sure there are many other acid fixers.

Wow we're getting a bit anylitical in this discussion. Over thinking it a bit.

 

[JoeV]

Mixing glacial acetic acid into a working concentration of stop bath is the single most dangerous activity in the black & white darkroom. For teaching kids and young people how to operate their own darkroom I much prefer dilute white vinegar.

 

[x-ray]

Mixing glacial acetic acid into a working concentration of stop bath is the single most dangerous activity in the black & white darkroom. For teaching kids and young people how to operate their own darkroom I much prefer dilute white vinegar.

Glacial acetic acid is getting harder to buy because of shipping. It's a very strong acid and agree it's quite dangerous. Glacial acetic is 99% where as photographic strength is usually ~28%.

Always add the acid to the water and stir as you add. Most acids mixing with water are exothermic and can release enough heat to boil water. Never add water to the acid! It's also a very good idea to wear goggles or face shield and rubber gloves when working with anything stronger than 28%.

 

[michaelwj]

The OP said in post #9 that he's using Formulary TF5. TF5 is alkaline unlike most fixers that are acid. Using an acid stop neutralized and ruins TF5. Formulary clearly states DO NOT use acid stop, it will ruin your fixer. Kodak fixers are fine with acid stop and I'm sure there are many other acid fixers.

Wow we're getting a bit anylitical in this discussion. Over thinking it a bit.

Yeah, I think the crux of my argument was it costs so little, why would you try to skip on what the instructions are?