Chemical Mixtures

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I just bought my own set of chemical (developer, stop, fixer, and photoflo) for developing my own film. I have a one reel tank and am just not exactly sure how to mix the chemicals. I know the developer has to be a 1:4 ratio of developer to water, but I only want to make enough for one roll at a time, instead of a whole gallon at once. Does anyone know the exact mixuters, for example (ounce of chemical: ounce of water). Thanks so much!

-- Colleen (icicle710@aol.com), September 10, 2000

Answers

Hi Colleen, This is very dependant upon the type of developer you have bought. Some like Agfa Rodinal tend to be quite easy to make just enough for a single roll where as others like Ilford ID-11 need to first be mixed using the whole package into what they call a "Stock Solution". You then can use a portion of the "Stock Solution + water" to make a one-shot solution you can discard. With stop bath it is just as easy to make a container full and reuse as it does not expire from sitting around but only from using it over and over. (at least it takes a very long time for it to expire if unused) As for fixer most folks also make a quantity that they keep and reuse. Fixer also has a life that is measured in how much film you develope and not so much on how old it is. Hope this helps.

-- GreyWolf (dwd@telusplanet.net), September 10, 2000.

Chemistry must always come with an instruction leaflet, so read this first! If nothing else is specified, ratios of liquids (1+4 in your case) are given in terms of volumes (not masses) to be mixed (because measuring volumes is so much easier). So if your tank needs say 250 ml to develop one 35-mm film (the quantity of solution needed is specified in the instructions of the tank, or even on the tank), one part is 250 ml divided by 5 (1+4), thus 50 ml. Add four parts, 200 ml, of water to get 250 ml.

-- Thomas Wollstein (thomas_wollstein@web.de), September 11, 2000.

Colleen, the bottom of your tank should say how many ounces or ml it takes to develop a roll.

Mine says 10oz for one roll of 35mm. For a 1:4 ratio that means you mix 8 ounces of water with 2 ounces of developer. If you were developing two rolls, it would be 16 ounces of water and 4 ounces of developer.

chris

-- Christian Harkness (chris.harkness@eudoramail.com), September 11, 2000.


Fixer does have a life after mixing, but it is many months, so it tends to not be a problem. To find out whether fixer is OK, when you do your first roll, drop the cut off leader from the film into some fixer, time how long it takes to clear. Write that time on the bottle. You fix your film for at least twice that time. Every few rolls test the clearing time again. Fix based on this new time. When the clearing time is double what it was with fresh fixer, dump it and mix new.

If you would tell us what chemistry you bought, we could give more detailed answers as to mixig small batches. But at someone else said, if the chemistry is in powder form you MUST mix the entire amount, making a stock solution, that you then dilute for use.

-- Terry Carraway (TCarraway@compuserve.com), September 11, 2000.


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