D-76 shadow detail

[David Lyga]

Kodak has long touted the fact that D-76 has the best (perhaps, 'unsurpassed' is more accurate) ability of any developer with regard to shadow detail. I did a test with some (discontinued) Polydol and I found this to be true by about half a stop, (with contrast being equal).

My question is 'Why?'. What component within the rather simple D-76 formula optimizes this shadow detail threshold? - David Lyga

 

[MattKing]

Kodak Film Comparison

Kodaks film comparison chart tells us that T-Max developer gives the most shadow detail, followed by X-Tol, followed by D-76

 

[David Lyga]

Thank you, but it is still one of the best for shadow detail. I was wondering what component in its formula (or formulas of T-Max or X-Tol) point towards this better shadow detail. - David Lyga

 

[cliveh]

I would have thought you can't really say that D76 produces more shadow detail. Surely there are too many variables just in lighting ratios/contrast, camera exposure and film development.

 

[pentaxuser]

Kodaks film comparison chart tells us that T-Max developer gives the most shadow detail, followed by X-Tol, followed by D-76

Interesting. I hadn't realised there was this ranking. Do we know by how much the 3 differ? For instance given the same scene, lighting, film etc would there be sufficient difference between the 3 prints for the viewer to see the difference i.e. it isn't just a difference that only a highly accurate sensitometer might just about detect?

Thanks

pentaxuser

 

[Bill Burk]

Haaa, Yes of course, it is correct exposure which produces the shadow detail.

But in terms of the developer, would you believe me if I said it was the Metol?

 

[MattKing]

Interesting. I hadn't realised there was this ranking. Do we know by how much the 3 differ? For instance given the same scene, lighting, film etc would there be sufficient difference between the 3 prints for the viewer to see the difference i.e. it isn't just a difference that only a highly accurate sensitometer might just about detect?

Thanks

pentaxuser

Here is the link: http://wwwtr.kodak.com/global/en/pr...wFilmProcessing/selecting.jhtml?pq-path=14053

As it provides a comparative analysis, rather than a quantitative analysis, I don't know the answer to your question.

I referred to it because David's initial post referred to Kodak saying one thing, whereas Kodak actually says something else.

But I think the answer to David's question is that the combination of ingredients in T-Max is what gives it the best shadow detail, not any particular single ingredient.

The chart is certainly a good argument for using X-Tol.

 

[pentaxuser]

The chart is certainly a good argument for using X-Tol.

Thanks and yes this was the chart that persuaded me to first try Xtol, helped I will admit, by its value for money compared to DDX which was then my developer

pentaxuser

 

[Bill Burk]

I did a test with some (discontinued) Polydol and I found this to be true by about half a stop, (with contrast being equal).

I would say that the fact you know to compare at equal contrast tells me you know what you're doing...

 

[fotch]

Here is the link: http://wwwtr.kodak.com/global/en/pr...wFilmProcessing/selecting.jhtml?pq-path=14053

As it provides a comparative analysis, rather than a quantitative analysis, I don't know the answer to your question.

I referred to it because David's initial post referred to Kodak saying one thing, whereas Kodak actually says something else.

But I think the answer to David's question is that the combination of ingredients in T-Max is what gives it the best shadow detail, not any particular single ingredient.

The chart is certainly a good argument for using X-Tol.

Wow, Xtol rocks.

 

[baachitraka]

The differences are not huge. Probably ~1/3 stop or less between D-76 and TMax.

Also keep in mind in the chart Kodak refers to "shadow detail", not differences in ISO speed. In some cases with a given film two developers can produce the same ISO emulsion speed but have slightly different toe shapes, which affects the rendition of shadow detail.

Meaning Xtol and D-76 may not give full box speed but on comparing with D-76, Xtol can give slightly more shadow detail when both are used to developed the film for certain contrast?


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[MattKing]

Meaning Xtol and D-76 may not give full box speed but on comparing with D-76, Xtol can give slightly more shadow detail when both are used to developed the film for certain contrast?


Sent from my Nexus 5 using Tapatalk

We are struggling here with some problems with momenclature.

The "speed" of the film will be the same in T-Max and D-76, because of the way that speed is defined.

But shadow detail will be rendered slightly more fully in the film that is developed in T-Max.

 

[RalphLambrecht]

Haaa, Yes of course, it is correct exposure which produces the shadow detail.

But in terms of the developer, would you believe me if I said it was the Metol?

not sure;developer formulation is a sensitive science with many not often fully understood ingredient interactions.We better leave that to the people at Kodak and Ilford.

 

[RalphLambrecht]

We are struggling here with some problems with momenclature.

The "speed" of the film will be the same in T-Max and D-76, because of the way that speed is defined.

But shadow detail will be rendered slightly more fully in the film that is developed in T-Max.

Really?:confused:

 

[David Lyga]

Kodak doesn't say that. In any case, it isn't that D-76 was/is unsurpassed for emulsion speed/shadow detail...

WRT Bill's post above, yes, metol is a good start, but not the entire story.

Actually, I tend to live in the past. 'Unsurpassed' was regularly used by Kodak back in the 60s and 70s (and maybe later as well). NOW they simply state 'excellent' shadow detail. Perhaps this is a bow to, and affirmation of, how extolled is Xtol developer in our current darkroom world.

I also did careful tests with Dektol diluted about 20x and that shadow detail was just as good as with D-76. But, again, Polydol was deficient by about half a stop (although its highlight separation was better than with either D-76 or highly diluted Dektol, or D-72). Configured as a portrait developer, this trait for Polydol just might not have been happenstance, as the somewhat superior highlight rendition with Polydol would have been a distinct, though subtle, benefit for such employment.

I think that D-23 would not do any better with shadow rendition as one poster, Bill Burk, seemed to infer: this metol-only developer seems to perform normally, albeit gaining gamma (contrast) does take more time.

I wanted to posit this question because there have to be tangible reasons for such differences. Your comments are revealing, although, perhaps, not yet definitive.

But I do take issue with the nomenclature comment posed by Matt King (correct me if I am wrong). Film speed is a determinant of different things for different folks. The history of such determination is diverse and even controversial. For me, however, it is that emergent shadow detail, in conformity within a consistent, predetermined, overall contrast index, which definitively rules the speed of a given film. - David Lyga

 

[David Lyga]

Granularity is largely determined by contrast, Michael, (and, of course, inherent film speed). That is why I used a static contrast index as an overriding necessity when comparing. Of course, you could develop in Dekol, not diluted, for 15 minutes in order to extract and match any claim to high speed and shadow detail out there. But you would have a mess to print!

Holding to this constant contrast index, the excess alkalinity in D-72 (Dektol) does not matter as far as grain and shadow detail are concerned. As long as you hold that contrast to manageable levels, that excess carbonate matters not in terms of grain. That said, the 'excess' HQ in Dektol also does not matter in terms of either grain or shadow detail, as far as my tests indicate. I would not hesitate using diluted, highly diluted, Dektol for development of ANY traditional B&W film.

I know that this is a deceptively difficult topic to parse, and perhaps there are different viewpoints out there, all equally legitimate. But I wanted to say this in order to counter some misconceptions. - David Lyga

 

[David Lyga]

You know,Michael, I have NEVER experienced a developer where the amount of grain deviated from what I said. I have always experienced grain being equal, regardless of developer, as long as the overall contrast index is the same. The hype about Dektol delivering excess grain is because it is HARD to not OVERDEVELOP film in Dektol.

If developers employ restrainer, that will certainly affect shadow detail (emergent shadows are 'seen' as the the same as fog by the developer; BOTH fog and shadow detail are suppressed with restrainers). - David Lyga

 

[DREW WILEY]

It's an utter fable. If you want more shadow detail, you need to get your Boeing 747 up to altitude quicker, a steeper ascent off the runway.
And 76 just doesn't do that quite as well as certain other developers like HC-110, DK50, and esp TMRS. 76 is better than some. So maybe the rumor came from a comparison of pre-packaging products way back when. Detail involves acutance and microtoanlity, and not just graininess. Less grain might equate to more mushiness, which is certainly the case with high-sulfite compensating formulas like D23. But
all of this is less an issue as sheer choice of film in the first place. No developer in the world will turn Pan F into TMax, for example, with
respect to shadow differentiation. Nor will there ever be a substitute for simply more surface area of film. But I largely gave up on all the
above soups once I started using pyro. Have my cake and eat it too.

 

[Sirius Glass]

Kodaks film comparison chart tells us that T-Max developer gives the most shadow detail, followed by X-Tol, followed by D-76

Dave rather than play junior chemist, why not use T-Max or XTOL?

 

[David Lyga]

Well, with due respect Michael, I hold onto what I said: Dektol will do just as well in that area. Maybe some day I will post results when I have time. Is there really such a difference between the two. Sure, Dektol has a lot more alkalinity and some larger percentage of HQ, but does that really matter if the dilution is appropriate? Maybe I am incorrect but I have yet to argue with results gotten from negatives developed in Dektol 1 + 19. - David Lyga

 

[Gerald C Koch]

Developing agents vary considerably in capabilities, D-76 is formulated with two; metol and hydroquinone. When used alone hydroquinone produces contrast but at the expense of full emulsion speed. It also has a large induction period where it appears to the user that nothing is happening. Metol on the other hand produces a low contrast image with full emulsion speed. The two are paired in D-76 to produce a developer which produces normal contrast with full emulsion speed. I might also add that here is nothing magical about the 2:5 weight ratio used in D-76. Somewhat different rations may be used in similar developers.

The actual difference in shadow detail is in reality rather small across a wide range of general purpose developers. The differences would probably not be apparent to the usual observer.

 

[craigclu]

It's been some years but my go-to D76 routine that helped "balance" my negatives (meaning to not have negatives with overly dense highlights but pull the shadow detail that was possible) was to spread out my agitation to 90 seconds, then use a single gentle inversion as my agitation technique (after a 1 minute initial set of very gentle inversions). This helped to build up shadow detail and help to restrain highlight blowout. I used it 1:1 and tended to shoot at 1/3 to 1/2 stop under film rated speeds.

 

[Bill Burk]

I think modern film just doesn't get grainy as easily as the old stuff. I also had "less" grain than I thought I would get when I tried to develop Tri-X in Dektol for what I thought would give me the most possible grain.

 

[Xmas]

Neither Tx nor 5222 are grainy I need to go to Fomapan 400.

 

[Alan Johnson]

IMO its ambitious to hope for an explanation of something like shadow detail in relation to the individual developer components.From "Theory of the Photographic Process", 3rd Ed, Mees & James p285:
"Levenson and James discussed the merits of several proposed systems for classifying developing agents based on ionic charge,chemical structure, adsorptivity and superadditivity. In view of the complexities involved, no all-inclusive correlation was found between photographic properties and any single chemical or ionic property of the developing agent."
It's an old 1954 reference, I have not looked at later books comments.