Mixing partial batches of b/w developer

[2F/2F]

Hello,

I would like to mix up one quart of stock D-19 from a one-gallon package, as I don't see myself doing 45 rolls in D-19 over the next six months. I am going to weigh out the whole amount and then quarter it to do so. However, I am wondering how long the leftover powder will last. I will probably keep the powder in some empty Kodak chemical bottles unless someone can suggest a better method. If it won't keep that long as an exposed powder, I might as well just mix up the whole gallon, which keeps for six months.

Thank you in advance.

 

[dpurdy]

I am experimenting with freezing mixed Dektol stock. I pulled one frozen liter out and thawed it and some chemicals had come out of solution and were floating around looking basically like when you first pour the dry chems in the water. I just added warm water to the desired dilution (1-1.5) and gave it a stir and all the chemicals went right back into solution and the developer worked fine all day.

If you have some liter bottles sitting around you might try it.. leave a bit of room in the bottle for liquid expansion when it freezes. I expect frozen the developer will last quite a lot longer... though I won't know that for sure till I pull out some more that is still frozen in 6 months and a year.

 

[Tom Hoskinson]

Hello,

I would like to mix up one quart of stock D-19 from a one-gallon package, as I don't see myself doing 45 rolls in D-19 over the next six months. I am going to weigh out the whole amount and then quarter it to do so. However, I am wondering how long the leftover powder will last. I will probably keep it in some empty Kodak bottles unless someone can suggest a better method. If it won't keep that long, I might as well just mix up the whole gallon, which keeps for six months.

Thank you in advance.

Kodak D-19 is easy to mix from its constituent dry chemicals. Just scale the recipe to whatever final developer volume you want.

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[2F/2F]

Kodak D-19 is easy to mix from its constituent dry chemicals. Just scale the recipe to whatever final developer volume you want.

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Hi, Tom. Thanks. I considered that, but I am missing a few of the ingredients, and I already have two 1-gal. pre-mixed packages that have been sitting here for a while.

Freezing is an interesting idea. I have, however, read Kodak recommendations not to keep E-6 chemical concentrates in the fridge, so I will wait for now on that idea until I have more info.

 

[gainer]

The major concern with mixing part of the powder is that the dry components may not be uniformly distributed in the original package. Mixing it all at once and dividing it into 4 containers for cold storage is a better idea IMHO. I don't think you need to go so far as to freeze it.

The precipitate falls out while the solution is cooling due to lowered solubilities of various components as the temperature falls. You have already distributed the components as required by dissolving them all at higher temperatures, so the precipitation will have no effect on performance as long as you warm each container before pouring out part of it's contents.

 

[Ian Grant]

Ilford ID-72 is a better alternative to D-19, being the PQ variation of D19b/ID-19 developer it has a far longer shelf life.

Gadget's suggestion of mixing & storing it divided is the best alternative using an existing packet.

Ian

 

[srs5694]

Some developers can be mixed at greater-than-recommended concentration (say, a 1-gallon packet to make 1/2 a gallon) and then diluted more at use to compensate. This can help extend the life of the stock solution. I don't know if this is practical with D-19, though. I've heard of people doing this with XTOL, and I believe some others. If you plan to freeze the stuff, this also has the advantage of requiring less storage space, although it would probably make it harder to get stuff back into solution when you thaw it.

 

[gainer]

See the Recent Chems side bar. It looks to me as if D-19 could easily be mixed at double strength for storage. Then your gallon size fits into half a gallon, or 4 pints, or even 8 half-pint bottles. I doubt that your projects would know the difference if you stored it in 500 or 250 ml bottles. I don't think freezing will be necessary, but you could freeze some of the bottles and refrigerate the others along with milk or soft drinks. Each time you use one, transfer one from the freexer to the refrigerator. Remember to use the whole bottle if there is precipitate in it, or warm it up until the precipitate dissloves.

 

[Larry.Manuel]

I've had good luck with dividing Kodak's powdered fixer into two batches, freezing the unused powder in the envelope, and mixing it later. The first thing I did was measure the whole bag's worth, by tablespoon, so I'd know how much is half. I know Kodak says that settling or uneven distribution of powders might be a problem. I shook the envelope well before opening. No problems.

 

[Photo Engineer]

My advice is do not ever mix a partial batch of chemistry from prepackaged dry chemicals!

PE

 

[Ian Grant]

Gadgets right, something like D19 can easily be made up double strength, typically I make up the PQ variants at 2.5X with no problems.

Ian