Classic D-76 formula : is there a way to improve it?

Ken Nadvornick

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Gerald C Koch said:
The maximum solvency of sulfite for silver halide occurs at about 75 g/l. I would decrease the amount of sodium sulfite to 75 g/l. This what was realized when Xtol was formulated. Use more sulfite and your just wasting money.
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Then for dedicated users of 1+1, would it make more sense to compound the stock solution at 150 g/l of sulfite in anticipation of that halving dilution? Or would such an increase at the stock solution level throw off other parameters of the formulation?

Ken
 

Roger Cole

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Sulfite is alkaline (thus D23 just using sulfite and Metol with no accelerator) so I'd think that would affect the ph significantly but that's just a WAG.
 

Ken Nadvornick

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Before dilution, I might think so. But what if there is no intention of ever using the stock solution undiluted? If it would only be used diluted 1+1, then 75 g/l of sulfite would always be the working strength. And all of the other ingredients would dilute down exactly the same as as they currently do.

I guess my question really is... pre-diluted, when stored as stock, would that extra 50g/l of sulfite do any permanent damage to the eventual ability to create a 1+1 diluted working solution? Or might there even be some benefits (enhanced preservation?) to that more concentrated stock solution?

Ken
 

Gerald C Koch

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If you are using D-76 1+1 or higher dilution then you are really not interested in the solvency effect. So I really don't see the concern.

The pH of D-76 is controlled by the amount of borax used.
 

Ken Nadvornick

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It was a hypothetical optimization question...

Ken
 

Athiril

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Gerald C Koch said:
Sorry, not a myth, go read Haist's book for more on the subject.
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Have you ever actually tried it? I don't see any of the people who keep repeating this online, all from the one source of information having ever tried it themselves.

"Go read this book" just isn't sufficient, you need to provide evidence, and reference it. Such as a link to the source information, or a quote of the source, and reference.
 

Gerald C Koch

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I am just not interested in getting into an argument over this matter. But I hardly call your two examples a studied controlled experiment. If one wished to measure the solvency of different concentrations of sulfite one would certainly not use an emulsion. Rather a measured amount of silver halide would be added to each of the sulfite solutions and the amount of dissolved silver measured chemically The nature of granularity is just too subjective and dependent on too many other factors to be used as a measure. In many respects Haist's two books are the last scholarly books on photography since the major film companies closed their R&D departments. Mr Haist is well respected in his field and I find no reason to doubt what he says.

The formula for D-76 was developed many years ago when the development process was not well understood. There was nothing magical about the choice of 100 g of sodium sulfite per liter. Developers of the time used 90 sometimes 125 g. As I mentioned the sulfite concentration of a modern developer like Xtol is much closer to the figure quoted by Haist. I do not find this to be a coincidence.
 
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Gerald C Koch

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There have been several attempts to improve the buffering of the formula. These formulas are given names like D-76x where x is some letter like c or d. A search of the web will turn up several variants. There is also Haist's suggested variant usually called D-76H which contains no hydroquinone.
 

Tom1956

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Tsk, tsk. Why do people band their heads against the wall thinking they can improve upon D-76 right out of the package? Oh, well.
 

Roger Cole

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Personally if I wanted to know the effect of more sulfite on developed film I most certainly WOULD use an emulsion. Now if I wanted to publish a scholarly paper on sulfite solvency effect, that's different. But I'm a photographer and I care about how it makes my photos look so that's what I would test, and I wouldn't care if my results disagreed with those implied by lab results of dissolving silver - I'd believe my own results and my own eyes. There's a time and place for practical empiricism and the darkroom is one such place.

Fortunately, I don't much care anyway because I find ordinary D76 at 1+1 to be quite satisfactory.
 

Xmas

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Hi Tom
Soup threads are always more interesting than bag or DSLR threads.

Back at page 1 the op said he was not getting the same results as the packet from Kodak gives...

The formula was for commercial use in dip tanks and assumed D76R? Kodaks packets are for stock bottles and don't drift the same?

If the op wants a 1:1 package signature from raw chemicals he needs to buffer better looks like he may also want finer grain.

If he uses a lower pH buffer that will slow the metol and may reduce grain at1:1 if he also adds more sulphite that will reduce grain as well.

Some of the dip tank people went to PQ there are lots of other options. Metol will upset some people.

It would be simpler trying another formula.
 

nworth

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The mere longevity of the D-76 recipe says that there isn't much that can improve it. All developers are compromises. The designer must balance grain, sharpness, film speed, stability, cost, toxicity, and other things. D-76 is an exceptionally successful compromise. Until recently, nothing could challenge it for overall quality. Recently, Xtol and DD-X have been seen as somewhat superior. There are many modifications of D-76 that address specific issues at the expense of others. D-76H (Haist's modification without the hydroquinone) makes some sense for one-shot users, but does not have the life or stability of the original. The buffered D-76d adds stability at the cost of complexity. Reduced sulfite adds sharpness at the cost of grain. One variation that deserves some attention was a competitor, Agfa 17. It retains most of the advantages of D-76 at the cost of some added complexity, and some people prefer the look of the negatives from it.

Agfa 17 fine grain film developer
This is a fine-grain develop recommended for roll, pack, and 35 mm films. It can also be used for obtaining soft gradation with press and portrait films. It is recommended for motion picture negative development.
Water 750 ml
Metol 1.5 g
Sodium sulfite 80 g
Hydroquinone 3 g
Borax 3 g
Potassium bromide 500 mg
Water to make 1 l
Do not dilute for use. Develop 10 to 15 minutes at 18C (tank) for fine grain films, 8 to 12 minutes (tray). Develop 12 to 20 minutes for Direct Copy, Direct Duplicating, and portrait cut films.

Replenisher (Agfa 17A)
Metol 2.2 g
Sodium sulfite 80 g
Hydroquinone 4.5 g
Borax 18 g
Replenishment rate: 15-20 ml per sheet, maintaining original volume.
 

Mark Crabtree

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I noticed the old Agfa 17 formula recently while trying to track down another (Permadol). The description sounded like this formula might be the commercially packaged Isodol. Do you, or does anyone else, happen to know? Is there any reason to suspect this is a softer working formula with slightly lowered film speed compared to D-76? That was my impression of Isodol, but might very well be mistaken. D-76 was very good at delivering full emulsion speed without excessive contrast at a time when the photography world's needs were moving in that direction.

I gave away a case of GAF Hyfinol this past fall which also fits pretty well. Pat Gainer was fascinated with that at one time and tried to replicate the formula. I think that info is here at APUG somewhere. I didn't see the point of using it over Xtol for small format, and it doesn't seem like the perfect formula for large format, so didn't really fill a need for me.


I believe this was mentioned before, but it sure sounds like what the OP wants is Xtol. You can scratch mix a version of that.
 

Ian Grant

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This is Agfa 44

Just a correction - the formula below is Agfa 44 also known as Agfa Ansco 17

Ian

 

Ian Grant

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For a number of years I used Adox Borax MQ and it's replenisher which is similar to Agfa 44 (agfa Ansco 17).

It gives slightly finer grain and better sharpness also a touch more films speed than D76, it's also cleaner working.

Ian
 

Paul Howell

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Ian Grant said:
For a number of years I used Adox Borax MQ and it's replenisher which is similar to Agfa 44 (agfa Ansco 17).

It gives slightly finer grain and better sharpness also a touch more films speed than D76, it's also cleaner working.

Ian
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I bought a case of Anco 17 on Ebay, used it for a number of years, really liked it, I agree with Ian, good grain, very clean working good shadows.
 

Ken Nadvornick

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Thanks for the straightforward answer, Michael. Appreciated...



Ken
 

Chris Douglas

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Yup Yup

I also mix D-76d and ditto everything Ken said. Its stable and lasts who knows how long. I use the published times for plus x and tri x without any problems. Without exception I use 1:1 one shot, and use the times for large tank with agitation once per minute.

Chris
 

john_s

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If one were not interested in replenishment, and using D-76 1+1 one shot, is there any benefit in using a formula any more complicated than D-76h which contains only metol, sodium sulphite and a little borax?
 

Ian Grant

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D76h is a Kodak Metol/Hyrdroquinone based variant of D76 with quite high buffering.

Haist referred to the fact that you could produce a variant of D76 with no Hydroquinone but didn't test the formula you refer to. However (there was a url link here which no longer exists)back in 1927 before they published the formula for D76. Haist would have known about this early Kodak fine grain developer.

Ian
 

Ian Grant

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My understanding is that Haist's H76 was a suggested possibility of a D76 type developer without Metol made in in a conversation with one ofthe authors of the the book the formula was first published in. It's not a Kodak formula, Haist would have known of the existence of D76h as part of the long term research into improvements of D76.

Ian
 

Gerald C Koch

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It is important to use the proper capitalization. For example, there is both a D-76h and a D-76H and the two formulas are not related.
 
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