Mixing D76 Options?Since the

[lhuhn]

I searched the threads but did not find the answer to the following question.

Since D76 is packaged to be mixed in 1.25 gallons of water and 1.25 gallon containers seem to be non-existent, I was wondering what people are doing to mix their developer. I have considered using 1 gallon or 1/2 gallon bottles and weighing out the powder proportionately, and I have considered mixing the stock solution at a higher concentration to fit a 1 gallon container and adjusting the working solution. The former seems to be the best solution to me. Any suggestions?

 

[photog_ed]

Freestyle sells a 5 liter storage bottle...

 

[Anon Ymous]

When I had to mix 5l developer (Xtol), I just got a smallish bucket, poured in 5l of water (measured with a graduate) and marked the level. Worked well enough. That said, doesn't D76 come in 1l and 1US gal packs?

EDIT: If your problem is where to store the developer, then just use several small bottles, filled to the top. It's much better than a single container.

 

[Trask]

I've used the concentrated option you refer to with Microdol-X, worked well. Just don't forget to dilute!

 

[Alan9940]

I mix it from scratch to the exact amount needed. No storage required and I don't have to worry about the pH changing over time.

 

[grahamp]

Don't split the powder - the proportions cannot be guaranteed to be equivalent. Just use a set of storage containers,with the last (smallest one) partially filled if necessary. Unless you need the full gallon plus of stock, you will only be using a fraction of the total stock at any time, and you can decant to maintain as many full containers as possible.

 

[gary in nj]

I just mixed Kodak Professional D-76 this week. The directions on the package were to mix the contents with 3 liters of water at 121 to 132F, yielding 3.8 liters, 1 Gallon.

 

[Harry Stevens]

What about mixing 5 litres into one litre splitting concentrate into 5 small plastic containers and then freezing them and when required for use drop one from the freezer into a container and make up to a 1 litre solution and bottle .........

 

[Gerald C Koch]

Don't split the powder - the proportions cannot be guaranteed to be equivalent.

+1

This bad idea keeps being brought up. It's been discussed numerous times. Due to uneven settling there is no guarantee that each of the portions will be identical in composition.

As far as mixing up the developer as a more concentrated solution is concerned D-76 contains 100 g/l of sodium sulfite per liter. This severely restricts its ability to completely dissolve the developer in higher concentrations. This thread seems to be a compendium of bad ideas.

First find a suitable mixing container. A plastic bucket works fine. THEN mix up the developer according to Kodak's instructions. One liter PET plastic soft drink bottles make good storage containers. Nothing could be simpler. You could also switch to HC-110 and mix a working solution as needed. HC-110 was designed to produce results VERY close to those of D-76.

BTW, where did the 1.25 gals come from in the OP?? D-76 cones in a 1 gallon size.

 

[MattKing]

BTW, where did the 1.25 gals come from in the OP?? D-76 cones in a 1 gallon size.

Sounds like someone has found some old, English or Canadian D76 that was packaged to make up an Imperial Gallon.

I find that a well rinsed 4 litre/US Gallon plastic milk jug works well for mixing up 4 litres/1 US gallon.

 

[David Lyga]

This is going to be VERY controversial but I have been doing it for YEARS and suffer no ill effects. (Yes, I am flying in the face of controversy here.)

A one liter size of D-76 contains 76mL (by volume) of powder. I simply buy larger sizes and mix what I want according to that measure. Theoretically, the powder is not to be separately mixed this way because there 'might' be more or less individual components in each batch. However, I think that a mathematician would state that the standard deviation from the stated formula would be trivial if the powder were measured and mixed in this way, so random are the powder's components. I have never had a problem. - David Lyga

 

[MattKing]

This is going to be VERY controversial but I have been doing it for YEARS and suffer no ill effects. (Yes, I am flying in the face of controversy here.)

A one liter size of D-76 contains 76mL (by volume) of powder. I simply buy larger sizes and mix what I want according to that measure. Theoretically, the powder is not to be separately mixed this way because there 'might' be more or less individual components in each batch. However, I think that a mathematician would state that the standard deviation from the stated formula would be trivial if the powder were measured and mixed in this way, so random are the powder's components. I have never had a problem. - David Lyga

As the D-76 powder isn't in any way homogeneous, home based mixing won't satisfactorily randomize it.
If you do it David's way, you will definitely add an extra source of unwanted variability.

 

[grahamp]

I used to regularly sub-sample ground rock powder for analysis. Obviously we went to a lot of trouble to test our methods as being statistically viable. The key element was to endure (oops 'ensure', though 'endure' is not a bad description!) thorough mixing. This was reasonably reliable with rock powders ground to a common particle size, though the mass differences in the minerals did cause separation over time if just left on the shelf. It is the thorough mixing which is the problem - the splitting is easy enough. (I'll happily discuss this off-thread).

The reason I would not advocate splitting powders in this case is that it is not necessary. A couple of gallons of stock solution is not that big a problem.

 

[David Lyga]

If you do it David's way, you will definitely add an extra source of unwanted variability.

And I promise you that that extra source of unwanted variability will be slight, indeed. Years of doing this attest to my confidence.

What you can do to mitigate that possibility is this: do a clip test after every mixing event to ascertain how much the mixture deviates from the unsullied formula. I think that you will find a timing deviation of less than 5%. - David Lyga

 

[Gerald C Koch]

I used to regularly sub-sample ground rock powder for analysis. Obviously we went to a lot of trouble to test our methods as being statistically viable. The key element was to endure (oops 'ensure', though 'endure' is not a bad description!) thorough mixing. This was reasonably reliable with rock powders ground to a common particle size, though the mass differences in the minerals did cause separation over time if just left on the shelf. It is the thorough mixing which is the problem - the splitting is easy enough. (I'll happily discuss this off-thread).

The reason I would not advocate splitting powders in this case is that it is not necessary. A couple of gallons of stock solution is not that big a problem.

One of the hardest things to do with quantitative chemical analysis is obtain a representative sample. Texts on the subject describe taking samples from say a box car. For example so much from the top third, middle third and bottom third. These multiple samples are then mixed together and samples taken from the mix.

 

[cliveh]

Good advice on this thread about not splitting the proportion of powder and when you mix it you have to wait until it is all dissolved. Don't be impatient. D76, just like the settlement of Draught Guinness, it is something you have to wait for.

 

[rthollenbeck]

In terms of convenience this is one of the major reasons I like HC-110. If you measure with a syringe (or other simalar device) you can mix straight from the concentrate to final dilution. The shelf life seems ALMOST unlimited this way. This helps keep the mess and dripage contained too.

Much the same thing with the pyro stuff I use now.

I was never disappointed in D76 but when I tried HC-110 at a friends urging and liked the results, the convenience above was an important factor in my decision to change.

Rarely do I come into contact with film devolpers, I wish I could say the same thing for when I use paper developers. But if I did, I think that is yet another reason for HC-110 over D-76 and a huge advantage over pyro.

Sorry to hyjack your thread, just something to think about. I'm sure not trying to sell anyone.

 

[lhuhn]

Thanks for all of the replies. I am embarrassed to admit that I rechecked the mixing instructions and i was incorrect, the entire package makes 1 gallon of stock solution, not 1.25 gallons as I had thought. I humbly apologize, but this thread was still informative to me as I was considering mixing smaller amounts to avoid wasting out-of-date developer.

After reading the posts in the thread my plan is to mix all of the developer as instructed on the package and split into 1 litre bottles for the best longevity. I appreciate all of the feedback!

 

[Gerald C Koch]

I think that I can say this for everyone. Glad that we could help.

 

[Harry Stevens]

And don't forget the ventalation or in my case the garden......

 

[Roger Cole]

Sounds like someone has found some old, English or Canadian D76 that was packaged to make up an Imperial Gallon.

I find that a well rinsed 4 litre/US Gallon plastic milk jug works well for mixing up 4 litres/1 US gallon.

I don't think so. I've never seen 5L packages of D76. I have an unmixed package to make 1 US Gallon now, and that's what I still see for sale:

http://www.freestylephoto.biz/1464817-Kodak-D-76-Film-Developer-to-Make-1-Gallon

Dead Link Removed

I don't know where this 5L D76 came from. Never heard of it, but it's been about a year since I bought chemicals.

 

[Roger Cole]

Thanks for all of the replies. I am embarrassed to admit that I rechecked the mixing instructions and i was incorrect, the entire package makes 1 gallon of stock solution, not 1.25 gallons as I had thought. I humbly apologize, but this thread was still informative to me as I was considering mixing smaller amounts to avoid wasting out-of-date developer.

After reading the posts in the thread my plan is to mix all of the developer as instructed on the package and split into 1 litre bottles for the best longevity. I appreciate all of the feedback!

Ah, that suddenly makes sense then!

 

[MattKing]

I don't think so. I've never seen 5L packages of D76. I have an unmixed package to make 1 US Gallon now, and that's what I still see for sale:

http://www.freestylephoto.biz/1464817-Kodak-D-76-Film-Developer-to-Make-1-Gallon

Dead Link Removed

I don't know where this 5L D76 came from. Never heard of it, but it's been about a year since I bought chemicals.

Roger:
The OP has acknowledged that his original post was incorrect, and that his D76 is actually designed to make up a US gallon.
My post was in reference to my youth . As I grew up in Canada, quite a few of the measurements I started with were Imperial, rather than US or metric. Certainly my storage bottles were 80 Imperial ounces (1/2 Imperial Gallon) and some of the chemicals may (I don't specifically recall) have been packaged in "Imperial" quantities. They were certainly in cans rather than packages.
I wonder what the equivalent experience would have been 40+ years ago for darkroom enthusiasts in the UK, who were supplied by Kodak Limited? I'm sure that Kodak Limited would have had less of the market than they did in the US.

 

[Harry Stevens]

One of the UK Kodak factorys in the 50s employed over 6000 people.

 

[iandvaag]

Good advice here about not subdividing a powder. I just wanted to add that I find it helps to use 2 different vessels -- I use a clean plastic bucket for mixing the powder until it dissolves, and then pour this into 1L glass bottles for storage. (PET plastic pop bottles work just as fine). I fill several 1L bottles to the brim, and if there is still some left over, I just pour it into another bottle (not filled to the brim). This last bottle is most prone to oxidation damage, so I use it first before moving onto the other bottles that are completely filled up.