High SBR Subjects: Pyrocat-HD EMA vs. D-23 1:1

thronobulax

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This was a subject with deep shadows on III and highlights on X. Scan of Agfapan APX100 processed as follows:

D-23 1:1 - APX 100 ASA 50 - 1 min prewash, initial 30 sec agitation, 5 sec agitation every 30 sec thereafter. 7 1/2 min total time @68F

Pyrocat-HD: APX 100 ASA 100 - 1.5:1:150 - 3 min prewash, initial 2 min vigorous agitation, 15sec agitation @12, 21 min - 30 min total time

These are scans of the negatives and are not perfectly matched but they show that both easily held the entire dynamic range nicely, albeit the D-23 loses a stop of film speed.
 

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It does seem to be true that reciprocity can generate a tortoise-and-hare situation and it does seem to be possible to follow both of them down an infinite rabbit hole. There may be no perfect solution.
Both of these negatives look perfectly printable. Well done. I take it as fundamental that our ultimate aim is to produce prints and that the negative is an intermediate tool, not an end in itself.

Things might be different if we were discussing transparencies. Photographers using transparencies are accustomed to sacrificing one end or the other of the brightness range.
 
It does seem to be true that reciprocity can generate a tortoise-and-hare situation and it does seem to be possible to follow both of them down an infinite rabbit hole. There may be no perfect solution.


What is interesting to me about this is that neither of the negatives in question required going down the expose-contracted development rabbit hole.

D-23 naturally compensates the highlights, and EMA - an expanded development method - protects both the mid-tone local contrast and reigns in the highlights.

I did a similar comparison with negatives done in divided Pyrocat-HD and Semistand Pyrocat-HD - with similar good results, at least from an initial scan of the negatives. (Nothing really counts for me until I silver print for final judgment.)

David Kachel has made the point in public and also in a private email to me that Zone system got contraction all wrong. If you do it the Ansel Adams way, you get muddy mid-tone local contrast. I think he is entirely right in this matter. Beyond the basics of composition and good focus, I have a basic model I want designed into all my negatives:

  • Proper shadow exposure
  • Preservation or expansion of local contrast in the dominant part of the image
  • Protecting the highlights from blocking
Having now explored (Semi)stand, EMA, divided development, and a compensating developer, I am entirely confident that it is possible to manage the last two of these very directly. One need only note which technique you are planning to develop with because it does affect film speed.

So, all I now worry about is the first - making sure I give the shadows sufficient exposure. This is the #1 sin I see committed with many negatives (my own included). I no longer care if the highlights fall on X or even above - these techniques solve that problem. Instead, I make sure my shadows are properly and fully placed and exposed.

As a general matter, if the dominant local contrast is OK in the scene, there is no reason to use low agitation techniques (unless getting full film speed is important for some reason). In the scenario where there is a high SBR and good local contrast, a compensating developer like D-23 1:1 or divided Pyrocat-HD is all you need. Low agitation is primarily indicated if you: A) Want to crank up local contrast and/or B) Want to exploit the adjacency effects these techniques produce.

Anyway, that's my story for the moment and I'd love to hear the experiences of others ...

Coda: It's also worth noting that these techniques will not solve the problem that a negative holds far more range of light than any paper could possibly reproduce. This is to your point about negatives just being a vehicle to get to a final image. What these techniques do provide, though, is more choices during the printing session about which range of light you want to reproduce in which sections of the print.
 
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Seems reasonable to me too. Good mid-tone contrast is really important. If a photograph is displayed on a wall, and you view it from a little distance away, what do you see? Not sharpness, or grain, or fine detail. You see the mid-tone contrast. Sharpness, grain and fine detail become apparent when you look closer, but overall contrast, and especially mid-tone contrast are apparent from the other side of the room. An essential part of getting mid-tone contrast looking good is to have the mid-tones high enough in value - not slightly dark. Ansel Adams showed the way to achieve this a long time ago. If there are bright subject highlights, then you give reduced development to stop them becoming too dense on the negative. This brings them down, which you want. But it also brings the mid-tones down, which you don't want. So you give more exposure. A stop more puts the mid-tones back up to where you want them. People, of course, have been doing this for years. It gets called "overexpose and under-develop" though Ansel pointed out that it is actually "correct" exposure and development for a subject with high brightness.
But which developer do you use? A compensating developer works best, by holding back the highlights but allowing the shadows and mid-tones to develop out. I have found that ID11 at a dilution of 1+2 or 1+3 works very well. Perceptol at 1+2 or 1+3 works very well, and so does PyrocatHD, with no visible difference between the last two, in terms of tonal rendition, grain or sharpness.

Alan
 
”Overexposed and under-develop...” is a good summary when addressing someone who only knows about box speeds. Perhaps we should be more careful and say something like “increased” and “reduced”.
Should we also be more careful about saying that we’ve established the “true film speed” ? We’ve done nothing of the kind; we’ve established what setting on our meter gives us results that we approve or find convenient.
Just another one of my hobby-horses. A hobby-pony, perhaps.
 
”Overexposed and under-develop...” is a good summary when addressing someone who only knows about box speeds. Perhaps we should be more careful and say something like “increased” and “reduced”.
Should we also be more careful about saying that we’ve established the “true film speed” ? We’ve done nothing of the kind; we’ve established what setting on our meter gives us results that we approve or find convenient.
Just another one of my hobby-horses. A hobby-pony, perhaps.

Perhaps more precisely, properly exposed and appropriately developed for the subject at hand.

We owe people like Adams and White a great debt for systematizing what had been more-or-less folklore before them. The idea of finding your "personal ASA" has much merit insofar as it captures the many variables in the image production process. The idea was to make photographic work repeatable, it was not to make it accurate. The problem, of course, is that the scene SBR will govern which developer and agitation method you select, which in turn will change the effective ASA of the film.

There is no question that my adoption of Zone System methods considerably improved my output. But something was still missing. What I now realize is that I was often sacrificing local contrast in the name of never blocking highlights. Using contracted development to squeeze the observed SBR into the negative in some formulaic way turned out to be a poor choice, at least in
many cases.

Having now more thoroughly explored the aforementioned techniques, photography - after 40+ years - is now revealing new possibilities for my work.
 
Thornobulax, Rüdiger Hartung has done some interesting work with stand developers see phone snap below
 

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I notice that the third-last paragraph mentions flashing.
I had previously wondered if double flashing might help. In-camera flashing to boost the shadows and in-enlarger flashing to control the highlights. I’ve never done both at once so this is speculation. Some testing would almost certainly be needed to avoid overwhelming the mid-tones.
I’m assuming that we are not trying to bring small specular highlights down to (say) Z8.
 
No, I like specular highlights they can give a print a little "sparkle".
 
Thornobulax, Rüdiger Hartung has done some interesting work with stand developers see phone snap below

His general observations are consistent with what I have found to be the case.

Do you happen to have a link to the original source of his comments. I'd like to look at the photos. Thanks.
 
His general observations are consistent with what I have found to be the case.

Do you happen to have a link to the original source of his comments. I'd like to look at the photos. Thanks.
Sorry I don't know how to link a facebook page, he posts on facebook in The Darkroom (celebratethegrain) as Rudiger Hartung, search for Mortensen technique. He also has a lot of his work on flickr as Ruediger Hartung
 
Is Rudiger under-exposing his film approx. -1to -11/2 stops, metering zone viii and then opening up his lense +1 stop to place his metered reading on zone vii. Then using stand development techniques to develop the film. All in order to get good separation in the upper mid and highlight tones. Have I understood that correctly?
 
Is Rudiger under-exposing his film approx. -1to -11/2 stops, metering zone viii and then opening up his lense +1 stop to place his metered reading on zone vii. Then using stand development techniques to develop the film. All in order to get good separation in the upper mid and highlight tones. Have I understood that correctly?

His explanation of how his metering is done was mystifying to me. His pictures (thanks for the link!) definitely show punched up mid-tone contrast which is a hallmark of minimal agitation techniques.

In my own case, I meter the very deepest of all the shadows for Zone III. Then:

  • If there is good local contrast AND the brightest highlight sits no higher than Zone VII, I process normally with Pyrocat-HD 1:1:100.
  • If there is good local contrast but I want to move the highlights up in a short SBR, I use Exterme Minimal Agitation with Pyrocat-HD 1.5:1:150.
  • If there is good local contrast but the brightest highlight exceeds Zone VII, I use semistand with Pyrocat-HD 1.5:1:200 or D-23 1:1.
  • If I need increased local contrast, irrespective of where the highlights live, I use semistand with Pyrocat-HD 1.5:1:200.

For normal development, I use box ASA -1/3 stop. For all Pyrocat-HD semistand development I use box ASA. For D-23 1:1, I use 1/2 box ASA.

I am still refining this as I've just begun to understand low agitation methods recently. No doubt, I will change some of this as I learn more. One thing I do not ever do any more is true stand development (only initial agitation, nothing thereafter). The risk of bromide drag ruining the negative is too high, and semistand gives me just as good a result. Modern films need at least one agitation at the standing midpoint in my testing.
 
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