Discussion in 'The Darkroom' started by benjyman345, Aug 23, 2007.
Should I use stop bath or just thoroughly wash out my developing tank after development?
I used to assume it was fine to just use water - and I think most of the time it's not going to cause any problems - but at times I found that fixing took longer, sometimes much longer than it should. Since I started using stop bath all the time I haven't had that problem once; the process has become more consistent, my negatives come out clear every time, and it saves me time on fixing and re-fixing. So yes I recommend stop bath.
I'm Canadian, live up north, and cannot get proper stop shipped to me for a reasonable price.
I've started using diluted vinegar as stop, and never been happier, my fixer lasts WAY longer (35-40%!!!, guesstimation) than when I just used distilled water.
Diluted vinegar? Plain old white vinegar? Diluted to what ratio?
Yes, vinegar is acetic acid which is used to make stop bath, a 5 to 10% solution should be fine. Most commercial stop baths use citric acid for the lower odor. You can also purchase both citric and acetic acid and mix your own from scratch, most acetic comes at 28%, glacial acetic is 98% so use it with great care. Hell, squeeze some lemons and use that.
HOLY CRAPOLA! PINHOLED NEGATIVES BATMAN!!!
Proper stop bath is 1.4% w/v acetic acid, and pure white vinegar is 5%. Use the cheap stuff, as it doesn't have any flavourings or salt in it.
I use 3:11, because it's close, although a bit dilute, and 60 mls of acid in 110 mls of water works well in my particular two roll development tank. (I don't actually mix it IN my tank).
It's no savings, as any proper chemical supply house (like jdphotochem), sells acetic cheaper in concentrate form, it just happens that shipping restrictions make a cheap chemical, expensive for me. It's the fact that it's a liquid I think, as a kilo of sodium cyanide powder costs less to ship than an ounce of relatively harmless glacial acetic. Crazy Huh!:er:
Not sure I follow you on that one, but a 5-10% solution of vinegar as I stated won't harm a thing.
Oh, well then, yes 5-10% won't harm a thing, but is rather more dilute than needed. Sorry, being a chem major I tend to think of things in the conventional way, we never use a % of a %, as that can cause confusion and/or convulsions-coma-death. We always speak of things in the final % of solution.... It's also important to consider the type of measurement used, like w/v, or v/v (weight/volume or volume/volume) etc..etc..
I am no chem major, but I do know from years of personal experience that using stop bath is better than just washing. Much better.
You can go either way as long as you do the same process each time, although I believe the use of a stop bath provides for more consistant results. Using a water bath instead of stop for either film or paper does not "stop" development at that time. So your time from developer to water to fix needs to be the same each time.
For my printing I use a water bath to help control development, stoping it in the shadows while allowing the highlights to continue developing. But, I always use a stop bath after. This compensating technique does not work with all developer/paper combinations.
Thanks for the tip on the dilution amounts. I will have to try that!
You can see my work at http://www.roxannajphotography.com
To bring this back, the Diafine box doesn't recommend using a stop bath. Any ideas why?
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