Weak D76H - What Went Wrong?

NortheastPhotographic · Mar 29, 2021

I am trying to use D76H which is of course a simplified version of D76. During my tests I've been pretty frustrated. I'm trying to mix 2L at a time (after a failure to make a 5L mix due to chems that would not dissolve).

Expanded to 2L the recipe is:

1500ml Water (I can get 110F out of my faucet)
5g Metol
200g Sodium Sulfite
4g Borax

These chemicals were recently purchased from Photo Formulary. In the 2L mix they dissolve well and stay in solution. The mixing experience is very similar to when I make D76. Yes I am doing them in the order listed above.

In my testing I have been making 1:1 working solutions to process in my Jobo ATL3 at 24C. But my test rolls keep coming back very under developed. So confused was I by this that I actually threw out the first mix and made a 2nd to test if it was something I did wrong, and no, just a weak developer.

Anything I'm missing here? The instructions pretty clearly state that you should use as you would D76 with the same times.

Tom Kershaw · Mar 29, 2021

NortheastPhotographic said:
The instructions pretty clearly state that you should use as you would D76 with the same times.

Have you tried mixing up a batch of standard D-76 with the Hydroquinone?

Tom Kershaw · Mar 29, 2021

If you're not fixed on D-76H, DS-10 produces good results. https://web.archive.org/web/2008093...er_Recommendations#DS-10_Fine_grain_developer

NortheastPhotographic · Mar 29, 2021

Tom Kershaw said:
Have you tried mixing up a batch of standard D-76 with the Hydroquinone?

I've made D76 with some of these same ingredient batches and had no issues. My understanding was that the Hydroquinone is basically non-active until some time passes with D76, hence the non necessity of it. But the baffling thing is this weakness. I even just tested my scale against another scale for accuracy, it's fine.

I overnighted some D76 as I'm running out. My goal was to have an affordable 5L mix that I could make for client work. D76H should fit the bill based on it's description...

Tom Kershaw · Mar 29, 2021

NortheastPhotographic said:
I overnighted some D76 as I'm running out. My goal was to have an affordable 5L mix that I could make for client work. D76H should fit the bill based on it's description...

I can see the point of this approach, but agree it is worth checking against a standard. Perceptol doesn't contain HQ but wouldn't be suitable for general work as the film speed needs to be set lower / accounted for in metering.

Lachlan Young · Mar 29, 2021

michael_r said:
The description in the FDC/DC of how the superadditivity of metol/HQ works is not really correct. It gives people the impression that unless the pH is high enough for HQ to be active on its own, it isn't doing much. This is very misleading.

This may be completely wrong, but as I understand it, the effect of the pH cycling on D-76 is such that the MQ/HQ relationship switches between an additive & superadditive relationship, not between an inactive HQ and superadditive HQ relationship - and Haist's D-76 conjecture is running on the idea that raising the amount of metol will compensate for what the HQ is doing under non-superadditive pH conditions in D-76. I would not be enormously surprised if the correct amount of Metol wound up being somewhere between 2.5 and 7.5g/l - it seems a lot like an attempt to reconcile D-76 with D-23. There's probably another subset of experiments to be done with following up some of the suggestions from the era when D-76 was young about using 20g/l borax (claimed to halve development time) or metaborate (claimed to quarter it) & seeing what it does with 1+3 (or 1+4) dilutions.

Pat Erson · Mar 30, 2021

NortheastPhotographic said:
The instructions pretty clearly state that you should use as you would D76 with the same times.

Yes but no.
Like you I made some HQ-less D-76 and I discovered you need to extend dev times. For my Hp5 I extended the time from 13 to 14 minutes. That was OK but 15 minutes could have been better.
Ever since I bought some HQ early this I moved back to make the traditional D-76 recipe.

Lachlan Young · Mar 30, 2021

michael_r said:
I partially agree. I would say pH instability of D-76 would switch it from superadditive to more strongly superadditive.

Another thing to consider is the effect of dilution on development time when a single developing agent is present vs a superadditive pair. OP indicated he used D-76H 1+1. Even if D-76 and D-76H were to have the same development times at stock strength, we cannot necessarily assume they would have the same development times at 1+1.

On the matter of dilution affecting development rate, I've attached some information that used to be in HP5+ data sheets - the Microphen/ ID-11/ Perceptol comparisons rather precisely demonstrate the stock/ 1+1 relationship differences for superadditive/ non superadditive developers (I suspect that the seemingly odd results for Ilfosol-S may have to do with the impact of high solvency on max density?). What is particularly striking is that stock Perceptol and stock ID-11 have almost identical development rate gradients (even stock Microphen is very close), but at 1+1, Perceptol has a noticeably shallower development rate gradient than ID-11. I imagine it would be fairly trivial to adjust Haist's D-76 variant at 1+1 to track D-76 at 1+1 - the question is whether to adjust metol or borax levels - on the understanding that it would probably significantly affect the stock solution development speed.

Lachlan Young · Mar 30, 2021

michael_r said:
Well, I'm satisfied we've properly diagnosed OP's problem.

Oh, and the other obvious factor no one seems to have noted - minimum stock developer volume at 1+1 needed to track with D-76 times is likely to be at least in line with the Kodak suggested 237.5ml/ 80 sq in for D-76/ Microdol-X - and if you're running 25xx Jobo tanks in an Autolab, that rapidly limits your film throughput.

NortheastPhotographic · Mar 31, 2021

Pat Erson said:
Yes but no.
Like you I made some HQ-less D-76 and I discovered you need to extend dev times. For my Hp5 I extended the time from 13 to 14 minutes. That was OK but 15 minutes could have been better.
Ever since I bought some HQ early this I moved back to make the traditional D-76 recipe.

Ding ding ding. I too made some regular D76 yesterday. It's working great.

The instructions in the dang FDC state that you can use D76H as you would D76. This to me does not imply that I need to change dilutions, times, the ingredients themselves for all love! It's a flawed recipe, or at least flawed description. Kind of leaves a bad taste in my mouth about the FDC, though OTOH I've had good results from their various paper developers I've tested. *Shrug*

TL/DR: Don't make D76H. Make D76. Also, Kodak: make 5L packets of D76. Or start making XTol that works. Or Adox: ship me a pallet of your new XTol.

Keith Tapscott. · Mar 31, 2021

ID11 deserves a mention.

NortheastPhotographic · Mar 31, 2021

Keith Tapscott. said:
ID11 deserves a mention.

Was unaware of the 5L ID11 mixes. Thanks for the tip!

Lachlan Young · Mar 31, 2021

NortheastPhotographic said:
Was unaware of the 5L ID11 mixes. Thanks for the tip!

Another vote here for the 5L ID-11 packs - consistent, easy to mix at just over 40oC. Have lost count of how many bags of the stuff I've mixed in the last few years.

Tom Kershaw · Mar 31, 2021

NortheastPhotographic said:
Kind of leaves a bad taste in my mouth about the FDC, though OTOH I've had good results from their various paper developers I've tested.

I only have the 1st edition of the FDC but it is not clear to me how much of the content has actually been practically tested. I'm not sure I've ever seen any images or data associated with the book.

Tom Kershaw · Mar 31, 2021

Another data point: Last autumn I wanted to do some close-up photography in 35mm with Delta 400 (rated @ 800) in low light conditions. Only needed for a few rolls but results were very good in Adox MQ Borax 1+1 (125ml stock + 125ml water) in my Jobo - that is per film, so below the Kodak recommendations for D-76.

Lachlan Young · Mar 31, 2021

@Tom Kershaw I don't think there's any doubt that less than 237.5ml stock developer per 80 sq in of film will do a better than adequate job - it just might not hit the exact contrast aim points for a manufacturer specified development time. Ironically, that may actually help place the negs at a more optimal contrast index than might have otherwise been intended.

Honestly, I think the whole MQ Borax 'thing' is a mirage - a slight drop in sulphite levels is not going to have as big an impact as people seem to assume - nor is it often being used in a manner where such differences can be separated from exposure/ processing variance.

john_s · Apr 1, 2021

Lachlan Young said:
..........
Honestly, I think the whole MQ Borax 'thing' is a mirage - a slight drop in sulphite levels is not going to have as big an impact as people seem to assume - nor is it often being used in a manner where such differences can be separated from exposure/ processing variance.

I suppose that's why people do 1+1.

Lachlan Young · Apr 1, 2021

john_s said:
I suppose that's why people do 1+1.

Halving or quartering the sulphite levels (1+1 or 1+3) will have much more significantly noticeable effects - 1+1 seems to have a fairly optimal balance of solvency & non solvent effects with many films, and may well land somewhere closer (though some would claim 1+2 for this) to what a well replenished developer would give, but with single shot accuracy/ convenience.

JWMster · Apr 1, 2021

Note that Tim Layton loves the D76-H at 7 minutes for HP5 shot at 250 ISO:
https://www.timlaytonfineart.com/blog/2020/12/kodak-d-76h-eco-friendly-b-w-film-developer-formula .

Tim's mixing instructions are given there, too. Your formulation is right, but he uses 125 temp and dissolves each ingredient before mixing them together. Worth a look or maybe a try? Note that he says he's doing this only one-shot and mixing at the time of use. I'm one shot, but like I think you're doing, prefer to mix a chunk and dilute for use. Mix-and-use every time just seems too much work? Yep.

FWIW, much as I've used PF - and they're good, I tried our NY outfit (Artcraft) recently and not only found their ship times faster to the east coast, but also found you can actually get someone knowledgeable on the phone. Prices were better, too.

Tim Layton also use D23 (which I use because it's only 2 ingredients and I had them on hand when I started). I found Tim's time for D23 for FP4 spot on at ISO 100. My first time with HP5 sheet film the other day? I shot at box speed and that appears to have been a mega mistake.

Weak D76H - What Went Wrong?

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