Using different brands of chemicals

Lucky Luke

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As I was looking to order some more developer, fixer and stop bath for printing I came by a much cheaper stop bath. I've always used Ilford Multigrade, Ilford RapidFix & Ilford Ilfostop. Is it a problem if I would change out the Ilfostop for a Afga stop bath? It saves quite a bit of money that I'd rather spend on paper.

The cheaper stop bath I'm looking at is Agfa Compard Stop Bath (Acetic Acid 60%).

I'm kinda assuming that it wouldn't be a problem but wanted to check before purchasing.
 

Martin Rickards

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In your case, there are basically two types of stop bath: acetic acid based complete with the smell of vinegar and the odourless based on citric acid. Both work equally well and it's up to the user to decide which to use. Other than that, there are several cheaper brands, such as Foma or Champion which should be equally as good.
 

Martin Rickards

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As far as its use as a stop bath is concerned, yes, its a question of smell. Your Ilford rapid fixer is also ammonium thiosulphate based which works more quickly than the non-rapid sodium thiosulphate based fixers, which are usually sold as crystals as opposed to the ammonium thiosulhate, which is sold as a concentrate. Sodium thiosulphate based fixers take longer to both fix and to be washed from the paper.. .
 

Nodda Duma

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If you’re going for low cost stop bath, you can mix your own. 1 level Tablespoon (15g) of citric acid in 1L of water works great (1.5% solution). Buy the citric acid in bulk and it'll be cheap. Use it one-shot or dump it with spent fixer depending on how often you develop film, since you won't have a preservative that keeps mold from growing (you could also add preservative and even add bromocresol purple as an indicator).

Or, dilute white vinegar to ~1-2% solution to make acetic acid - based stop bath. Store bought vinegar is typically 5% in the US, which can be diluted 4 oz vinegar into 12 oz water to make 16 oz of stop bath. In the Netherlands I think stores carry 10% vinegar, so mix 2 oz vinegar into 14 oz water. Pretty cheap even if you use it one-shot.

But, to be honest, a bottle of concentrated indictor stop bath should last you many years if you don't toss working solutions until it is exhausted.
 

jvo

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i also consider the manufacturer... cost is only one factor, (often a minimal difference). i want to support the manufacturer who is making products for my type of photography and willingly pay a bit more.
 

RalphLambrecht

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I always mix and match processing chemicals as I see fit; not an issue but ,I make sure not to mix film and paper chemicals and I stay away from fixers containing hardener.Other than that, go for it or consider mixing your own from bulk chemicals. With that ,there is little or no price benefit but you always have fresh processing chemistry and formulae are readily available.
 

MattKing

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There is a functional difference between the relatively odorless citric acid based stop baths and the more smelly acetic acid based stop baths - at working strength, you can safely store the acetic acid based versions for a fairly long time, whereas the citric acid based ones will encourage the growth of mould. So if you tend to re-use your stop bath until it loses potency, and like to store it between processing sessions, the smelly stuff is better.
Otherwise, feel free to mix brands.
 

Doremus Scudder

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Matt is 100% on the mark.

I use an acetic-acid stop when printing so I can keep the working solution in a tray for a week without worrying about mold/slime. I normally have 2-4 liters of solution in a tray at a time. When developing film, I normally toss the stop after the day's work, so citric acid works fine. I have, and use, both. Mixing brands is no problem.

Best,

Doremus
 

MattKing

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Ironically, Doremus and I do things exactly opposite to each other .
But that is entirely due to the odour - I develop film in a well ventilated and well lit kitchen, while I print in a temporary darkroom that is a bathroom most days, and requires one to work relatively close to the trays.
 

Mainecoonmaniac

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I use a tablespoon of food-grade citric acid per liter of water. Works great, cheap and no smell. I toss it after every print session. I think with liquid stop bath, you have to pay for the bottle and transportation costs. Nothing wrong with pre-made stop either.
 

winger

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Lucky Luke said:
Ah, so the main difference between acetic acid based and citric acid based is the smell?
Click to expand...
And add Sprint stop to the list - they add a vanilla scent to acetic so it really doesn't smell bad.
 
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