Do emulsions "die"?

jstraw · Nov 28, 2006

I did a film speed test for some very-old TMAX 400, 4x5. I exposed 4 sheets at 1/125th and at different apertures to simulate speeds of 200, 300, 400 and 800.
I processed these, along with an unexposed sheet (to determine B+F density) in D-76 stock for 7 minutes.

All five sheets look identical. No denisty above (presumable) B&F. No hint of a film-holder border on any of them.

Possible causes:

Dead developer (this is possible *)
Dead film (never heard of such a thing)
Dead shutter (it may not be accurate but it opens)

* I used 1/10th (by weight) of a package made to mix 10 gallons of D-76, to mix a gallon of stock. I bought this at auction. It's possible that the componant chemistry is not mixed but added to the bag sequentially so what I took off the top wasn't actually, functional D-76 powder. The powder had clumped into a block, which I had to break up some to get what I used. It's also possible that the bag didn't have a perfect seal and the contents have deteriorated.

Thoughts?

Photo Engineer · Nov 28, 2006

No film or paper truly dies.

They can lose speed or go into fog, but they will never leave you without something there.

You usually will not like what you get, but who knows, sometimes the results can be surprisingly good.

PE

Gerald Koch · Nov 28, 2006

jstraw said:
* I used 1/10th (by weight) of a package made to mix 10 gallons of D-76, to mix a gallon of stock.

You should never mix up part of a powdered developer. The reason being that you can never be sure that the components are evenly dispersed. It is entirely possible that most of the developing agents never got into solution.

jstraw · Nov 28, 2006

I guess I'll shoot a roll of 35 and test the developer. If it's ok...then I'll ummm....geesh...

jstraw · Nov 28, 2006

Gerald Koch said:
You should never mix up part of a powdered developer. The reason being that you can never be sure that the components are evenly dispersed. It is entirely possible that most of the developing agents never got into solution.

Ok, so that nine pound bag may be a lost cause because I skimmed off the top 10% of it.

I have another nine-pounder. Can I blend that powder, then divide it up?

Nicholas Lindan · Nov 28, 2006

jstraw said:
D-76 powder. The powder had clumped into a block, which I had to break up some to get what I used.

If it has clumped into a block it has in all probablility gone bad. It wouldn't happen to be orange/brown in color or have an unpleasant odor?

jstraw · Nov 28, 2006

Nicholas Lindan said:
If it has clumped into a block it has in all probablility gone bad. It wouldn't happen to be orange/brown in color or have an unpleasant odor?

No odor and a nice nearly-white color.

Photo Engineer · Nov 28, 2006

Do not use the partial bag mixed with a full bag. There is no way of knowing what the mix will be.

PE

jstraw · Nov 28, 2006

Photo Engineer said:
Do not use the partial bag mixed with a full bag. There is no way of knowing what the mix will be.

PE

Oh, I know. I wasn't clear. I'll pitch the rest of the first bag. The second bag, can I mix the powder to evenly distribute the ingrediants then divide it into quantities for mixing one-gallon batches?

kb244 · Nov 28, 2006

The only powder developer I know of that works well being mixed in parts, are those that come packaged with all the solid ingredients in separate containers (like how some places sell their own batch of Rodinal)

Also I've developed rolls of film as old as 60 or 70 years old, the emulsion can slowly "die" but typically in the behavior of fogging over anything noticible. For example I find that most roll film thats older than 40 years old, typically only the first two or three frames near the center of the exposed roll will survive the development.

kb244 · Nov 28, 2006

jstraw said:
Oh, I know. I wasn't clear. I'll pitch the rest of the first bag. The second bag, can I mix the powder to evenly distribute the ingrediants then divide it into quantities for mixing one-gallon batches?

You could just store the stock solution in a well secured glass container with a metal cap, and mix off your working solution in smaller bottles, to be remixed when that working solution goes bad ( I do this a lot with dektol ).

jstraw · Nov 28, 2006

kb244 said:
You could just store the stock solution in a well secured glass container with a metal cap, and mix off your working solution in smaller bottles, to be remixed when that working solution goes bad ( I do this a lot with dektol ).

10 gallons is a lot to store. That'll fill a Combi-Plan 35 times over. For sheet film, D-76 stock is working strength.

Gerald Koch · Nov 28, 2006

Trying to mix up a partial batch really is a false economy. Trying to mix the powder to get uniformity will stir up a lot of chemical dust which isn't good. You might give away some of the mixed developer to other photographers. Or you could use what you can within the expected life.

jstraw · Nov 28, 2006

Gerald Koch said:
Trying to mix up a partial batch really is a false economy. Trying to mix the powder to get uniformity will stir up a lot of chemical dust which isn't good. You might give away some of the mixed developer to other photographers. Or you could use what you can within the expected life.

What would be the expected life? I could get two five gallon buckets with lids.

Photo Engineer · Nov 28, 2006

jstraw said:
Oh, I know. I wasn't clear. I'll pitch the rest of the first bag. The second bag, can I mix the powder to evenly distribute the ingrediants then divide it into quantities for mixing one-gallon batches?

Never, ever mix a partial batch of a powdered premixed developer or fixer.

Never, ever mix a partial batch of a liqid kit that contains crystalline material.

Those are two absolutes I learned over my long career in photography.

PE

Gerald Koch · Nov 28, 2006

I believe that Kodak says that unused developer will keep for 6 months in full, well sealed bottles. Containers should be glass or PET plastic (the recycle number in the triangle should be 1), buckets are not satisfactory.

jstraw · Nov 28, 2006

I will wait to mix up the second bag till I have enough PET to store 10 gallons. 35 combi-plans is only 210 sheets. I should be able to make a good dent in that in 6 months.

What's a film for which D-76 would be a preferred choice?

Maybe this is a lot of bother for a bag of D-76 that came on a pallet of goods I got for 35 bucks. :rolleyes:

kb244 · Nov 28, 2006

jstraw said:
10 gallons is a lot to store. That'll fill a Combi-Plan 35 times over. For sheet film, D-76 stock is working strength.

Hrm, well I missed the '10 gallon' part, also why would one buy 10 gallon powder mix if they're not just gona go ahead and mix it into a big vat for immediate use?

DBP · Nov 28, 2006

Old emulsions never die, they just slowly fog away.

jstraw · Nov 28, 2006

kb244 said:
Hrm, well I missed the '10 gallon' part, also why would one buy 10 gallon powder mix if they're not just gona go ahead and mix it into a big vat for immediate use?

See post #17.

Gerald Koch · Nov 29, 2006

D-76 is probably the all round developer and film manufacturers publish development times for it even if they don't mention any other developer. D-76 can be used FS or diluted up to 1+3. There is probably no one film that is better than any other in this developer. However, I know that people do have their own personal favorites.

gainer · Nov 29, 2006

10 gallons are about 38 liters. You might be able to dissolve the powders in 5 gallons of very hot water, put that into 20 quart bottles, and dilute it at time of use. Some will probably have settled out, so you would have to use a 2 quart container and make sure you got all dissolved. By the time you get all the mixing containers you need, whichever way you do it, the additional expense for a liter or quart of D-76 would be greater, I think, than the cost of separate chemicals, metol, hydroquinone, sodium sulfite and borax to make a liter. If you are consistent in your measurements, you don't need a balance. There are teaspoon formulas, and some years ago I did some tests to see how much variation of each ingredient could be tolerated before the result became noticably different from D-76. I'll dig up the article if I can find it. It was in Petersen's Photographic, April, 1973. Most of my friends at the time thought it was an April Foll joke.

Bob F. · Nov 29, 2006

To keep 10 gallons fresh, you will need some kind of floating lid or decant in to multiple fizzy pop bottles filled to overflowing (glass would be even better, but the cost of buying the bottles would be high compared to using washed out large size Cola bottles). It should keep for well over a year in the pop bottles. ID-11 did for me.

Can't say how long before you start to see a loss of activity, but I did not notice any (but then, it would have to be pretty obvious for me to notice it...). My ID-11 was as clear as the day it was bottled and put in a dark cupboard 14 months previously .

Cheers, Bob.

jstraw · Nov 29, 2006

17, two-liter bottles will be collected.

I'll have to be able to desolve all nine pounds in a 5 gallon bucket for this to work, since I have nothing bigger. Then I'll measure a liter of the double-strength solution into each bottle, top them off with water and seal them with Saran Wrap under the lids.

Paul Howell · Nov 29, 2006

As inexpensive as D 76 and D 11 are this seems like a lot of work.

Do emulsions "die"?

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