How much stock solution do you mix?

[John Kasaian]

I've been mixing gallon jugs of the stuff, but during the past year I've had too many experiences with stock solutions going bad, so I'm thinking of switching to 2 liter jugs instead.
How much stock solution do you mix at a time?

[Michael Clark]

I mix the gallon packets of paper and film developer chemistry, and buy the liquid F-5 fixer concentrate in one gallon jug. During the summer is when I start to worry about having to much mixed up and going bad, not so much during the winter. The concentrate fixer seams to hold up fine and its kept in the garage during summer. I think half gallon bottles would be better, it takes me about a month to go through a gallon of stock solution developer, but some times more.

[stawastawa]

I store stock solutions in small containers, so less likely to get disturbed and oxygenated and go bad. I have moved away from storing chemicals in less than 1/2 gal containers unless I know I am printing large often.

[Doremus Scudder]

Almost all my chemicals for film developing and printing get mixed "one-session" or for two consecutive sessions, then get tossed.

For film developing, my developers of choice are all in concentrated, long-shelf-life stock solutions: PMK, Pyrocat, HC-110, etc. I use theses one-shot. Occasionally I have a small amount of PMK go bad on me before I can finish an entire bottle of concentrate, but the loss is small.

Print developers seem to last fairly well in stock solutions. Bromophen and Zone VI (and even Dektol) developer last six months to a year in stock solution if stored carefully (I do use gallon jugs). Liquidol and Ansco 130 are really long-lived. These, of course, get mixed down into working solutions that I use for one day or a bit longer, depending on the individual developer and my throughput. I more and more tend to mix basic developers from scratch just before use (D-72, Selectol Soft, etc.). These, again last for a session or a bit more.

Fixer is from liquid concentrate, either Ilford Rapid Fixer or Hypam or TF-5. I only mix what I need for the session and keep track of capacity. Only rarely have I had to discard fixer concentrate due to sulfurization because of age.

If you use acetic-acid stop, you can mix it and use it till it is exhausted without worry. I mix citric-acid stops for one-two sessions since they store poorly.

My selenium toner gets filtered and replenished, as I have described here often. I mix wash-aid from scratch one-session.

Best,

Doremus

[Pete Oakley]

I use the Patterson Orbital system so I only need 300ml of liquid in the tray for 4 4x5, 2 5x7 or 1 8x10. I only mix 1 or 2 litres of D-76H as I use this 1-1 and 1 or 2 litres of TF2 fixer depending if I have roll film to process as well. I always leave the developer overnight before I use it but I can't remember why, if I ever knew.

[esearing]

I am an infrequent practitioner so I seek longevity of stock and/or working solutions. Trying to remedy that by doing a little every month. I also only shoot a few 4x5 sheets a month and print mostly 8x10 so do not need large volumes.

Film developer I use one shot and buy in 1 liter size HC-110, Pyrocat HD in Glycol.
Fixer a gallon of TF4 or Ilford rapid fix seems the most economical for my needs. working strength I make a Liter at a time and sometimes replenish if working frequently.
Print developer mix a gallon stock and dilute from there. Ethol LPD seems to hold up even diluted to working strength for a few months.

[chassis]

I am migrating to 0.5 liter bottles after 35 years of using gallon jugs. This is after starting C-41 processing myself, and mixing several gallons of each chemical, storing in 1 liter and 0.5 liter bottles.

I bought bottles at K-Mart. Sweetened drink (vitamin water, for example) bottles are made with PET (good, meaning low, oxygen permeability) and reasonably good closures (screw caps). 1 liter bottles are available for US $0.69 each. About the same, or less, than can be found on line, after shipping cost is included.

I use D-76 one shot, diluted 1+2 from stock solution. 1 piece of 4x5 film uses 3 ounces of stock solution in a BTZS tube, using my stand development method. This means I can get almost 50 sheets of 4x5 film processed with 1 gallon of stock developer solution. So in the ball park of US $0.02 developer cost per sheet of B&W film.

Using four 0.5 liter bottles is a good way for me to preserve developer freshness with the monthly volume of film I process.

p.s. For C-41 processing I use mainly 1 liter bottles, because of my development method. I use a Paterson tank for one sheet of film, and this requires about 750 ml of fluid, per each chemical. So I decant 750 ml into the tank, follow the process, then pour the solution back into the 1 liter PET bottle. My C-41 process is not one-shot. This may change as I improve my workflow.

[Gary Samson]

I use 1.5 liter glass wine bottles with stoppers that allow you to create a vacuum after use. This has been a very successful way for me to keep Pyrocat M for months after mixing. I have never had developer failure using this method.

[Luis-F-S]

The least quantity possible. Still I end up throwing a lot of it away. L

[Jim Noel]

I mix no stock solutions. I mix appropriate quantities at proper dilution as I prepare to use it. This is true of both liquid concentrates and powders such as Dektol. Those which I mix from basic chemicals are mixed in one shot usable quantities.

[Leigh]

I mix appropriate quantities at proper dilution as I prepare to use it.
This is true of both liquid concentrates and powders such as Dektol.
You absolutely cannot mix partial quantities of powdered chemistry because there's no way to guarantee the proper ratio of component chemicals in a partial volume of powder.

This has always been true of any powder consisting of two or more chemicals.
It's true throughout the chemistry world, not related to photography or any other specific application.

- Leigh

[HMG]

When I use powder chemistry, it's always 1 gal batches since smaller sizes are so expensive given the quantity. After mixing, I decant into .75L brown glass bottles from a rye whiskey I like (what I won't do for art!). Of course, clear glass in the dark would be just as effective. The narrow necks leave very little exposed to air until the bottle is being used - I suppose a shot of nitrogen or even CO2 would help even more. We can argue about the permeability of one plastic vs. another, but no argument about glass.

I've found stock D-76 and Dektol to last at least 6 months when stored like this.

[Jim Noel]

You absolutely cannot mix partial quantities of powdered chemistry because there's no way to guarantee the proper ratio of component chemicals in a partial volume of powder.

This has always been true of any powder consisting of two or more chemicals.
It's true throughout the chemistry world, not related to photography or any other specific application.

- Leigh

I have been doing this for more than 60 years and have never had a problem. When I first started ding this I ran a comparison test between this method and diluting from a stock solution. Within a few days the films developed in diluted stock solution began to show less density in the highlights than those developed in my method. I have not seen any reason to change over the years.

[aeyb701]

I've used the Jobo C-41 Press Kit powder 1 litre chemistry mixed up and stored indoors room temp in brown plastic bottles TWO YEARS , with only a nigh-on imperceptible green shift. Still good contrast.
Most wouldn't have tried this but my subjects were forgettable anyway so what the heck, if only to report my findings to others, and feel more secure in leaving the stuff sit when G from one interest to another, coming back a few months later.
I'll be trying it with one litre bottles of Tetenal E6 that I mixed in October 2016 and let people know the outcome; that from the 5-litre package of concentrate I received in 2007! Got good results not having made working solutions till 2015.https://uploads.tapatalk-cdn.com/20170212/c6de98e7f2dd76d7f86645f7f8a527e9.jpgvoigtlander 9x12 Bergheil plate camera/ 135 Heliar lens with rada 120 film holder and E 6 film, stock solution kept unused for 8 years before making up working solution and processed using Jobo processor CPE2 or whatever.
Jon Archibald
Peterborough ontario

Sent from my iPad using Tapatalk

[neil poulsen]

I mix a gallon at a time of stock. I got into mixing more than that at one time for a bit. But from what I understand, package to package variability is small. So, I stopped doing that. I don't do a good job of keeping track when I mix and discard D76 stock. I toss Dektol, when it begins to look dark. At the first sign of darkening, D76 gets tossed.

Working fixer goes to the recycle, when it's depleted. I use a bottle of "checker" to determine when that's occurred. So, stop and fixer go back into working storage bottles at the end of a session.

Dektol working solution gets tossed at the end of a session. I might use D76 over two sessions, depending on how much film I've developed. But, no longer.

I should get some removable labels to date when I mix either D76 or Dektol.

[EdWorkman]

I mix the 5 liter bag of Xtol in a gallon jug- probly was originally full of wine, but I don't remember.
A little algebra gives me the correct amounts of water and stock to achieve final dilutions 1:1 1:2 or 1:3.
Then the rest in the gallon jug goes into as many [glass[ 750 ml wine bottles as needed, or those small apple juice bottles- just about the only glass bottles in the grocery any more

[HMG]

Another option, if you want to store small quantities, are beer bottles using bottle caps and a capper (https://www.midwestsupplies.com/royal-crown-bottle-capper). There are even oxygen absorbing bottle caps but I don't know how well they work.

[jnantz]

hi john

when i used to buy ansco 130 once a year i would mix up 5-6 gallons all at once, they lasted for at least a year.
i went from 6 to 5 when it took a years and a few months ... and the developer changed color a little bit
now i mix from scratch about a gallon of dektol. its in a glass brown bottle, it still seems good, i'll know for sure in
a day or 2 when i make a print or process some film.
i was thinking of putting a whole bunch of the powdered chemicals for 1 gallon of d72 in a big pickle jar and shake it up like
i have done for caffenol c .. and figure out how many teaspoons /tablespoons in a gallon and mix as much as i need just when i need it.
i have heard warnings for years but i figure most everything else i have been warned about, the dire circumstances never came true
its just a print anyways, i will be able to see pretty fast, and if it is for a sheet or roll of film, it will be mixed with caffenol c so i know it will still develop
just with a little less contrast.

[James Pierce]

2 Gal tanks with floating lids - I mix up two bags of D76 or Dektol at the same time... it lasts many months.

[Duolab123]

I buy 2,4,8,16,32 ounce brown PET bottles mix 5 L of Xtol. Fill 3 or 4 quarts to start divide the rest. Never store stock solutions except in absolutely full bottles. My stock Xtol lasts over a year at 68 to 70 F

http://www.freundcontainer.com/boston-round-plastic-bottles/p/3371B07ABR

These guys have every container on earth, they will sell you 1 or 1 million. Great service, fast I am done messing with big j**gs, uh I mean bottles ;)
Mike

[Duolab123]

I've used the Jobo C-41 Press Kit powder 1 litre chemistry mixed up and stored indoors room temp in brown plastic bottles TWO YEARS , with only a nigh-on imperceptible green shift. Still good contrast.
Most wouldn't have tried this but my subjects were forgettable anyway so what the heck, if only to report my findings to others, and feel more secure in leaving the stuff sit when G from one interest to another, coming back a few months later.
I'll be trying it with one litre bottles of Tetenal E6 that I mixed in October 2016 and let people know the outcome; that from the 5-litre package of concentrate I received in 2007! Got good results not having made working solutions till 2015.https://uploads.tapatalk-cdn.com/20170212/c6de98e7f2dd76d7f86645f7f8a527e9.jpgvoigtlander 9x12 Bergheil plate camera/ 135 Heliar lens with rada 120 film holder and E 6 film, stock solution kept unused for 8 years before making up working solution and processed using Jobo processor CPE2 or whatever.
Jon Archibald
Peterborough ontario

Sent from my iPad using Tapatalk

I've had really good luck with Tetenal E6 longevity. I'm still using a 5 liter kit that I split up over two years ago. I'm doing a test on storing some Kodak C-41 working solution developer replenisher. I have it stored in divided 120mL bottles. Seems to keep forever at 65F in full bottles. Just a little air and it's dead. Oxygen is wicked stuff doesn't take a lot to destroy the developer.

[chassis]

There is a thread on APUG with a recommended list of Kodak Flexicolor C-41 chemicals to use. There is a thought that the Kodak Flexicolor chemicals are thought to be longer lived than others. When stored full to the brim in PET bottles, the solutions can last quite a while. I am working through my first installment of these chemicals from the APUG advice and am a satisfied practitioner so far.