Maximum Black and tone, sharpness and grain

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I am doing film tests to determine true speed by testing for zone I and to determine and control contrast by testing for Zone VIII. I have, however, come across a few threads by very knowledgeable contributors who have thrown a shadow of doubt over my conceptions. John Hicks writes that for Delta 3200 "The EI 1200 spec is "true" speed, .10 DU above fb&f" but that "the "sweet spot" is EI 2000; tonal rendition is very nice and the grain isn't horrible." Similarly, regarding prints, Conrad Hoffman writes that "Personally, I find trying to reach absolute maximum black requires denser negatives that compromise tones, sharpness, or grain, in other areas of the print, but it's certainly determined by what effect you're after :-)" (Hope you don't mind my citing your names?!)

I was always under the impresstion that determining Zone I at something like .1 density above fb+f would give the most complete tonal rendition and could thus be considered true speed. However, how can this compromise tones, sharpness, or grain?

-- Raja (d60w0635@ip.media.kyoto-u.ac.jp), April 08, 2000

Answers

Hi Raja,

There seem to be two ways to go about this, and they both work. You can get one of the several excellent zone system books that have been mentioned by people here. Follow the methods and you'll arrive at a pretty good calibration that matches you E.I., development, and printing methods. Hopefully you'll also become good at previsualizing how a given scene will go through the process and look on the final print, then be able to alter the process to suit your vision. That's one way, and it has a long history of working well for many people. Another path is to study traditional sensitometry. Again, there are several very good books for that. Even if you go pure zone system, I think everyone should have a copy of Photographic Sensitometry by Hollis N. Todd & Richard D. Zakia on the shelf to refer to in time of need! Your materials don't know or care how you arrive at your exposure and processing numbers- they simply react according to the laws of chemistry and physics. Now, to the question at hand. The technical definition of film speed is based on a specific density above base+fog, but there's nothing saying that that number will give you the results you're after. It just provides a consistant measurement so you can compare apples with apples when evaluating films. The problem I always have is judgement; what part of the scene should I place just above fb+f- how much shadow detail do I want? On the maximum black thing, it takes a substantial exposure to produce the absolute maximum black a paper is capable of. That means that shadows move further up (or down, depending on how you draw it) the paper curve, and shadow detail will be lost. IMHO, not usually a good thing. The midtones and highlights of the negative will have to be denser than they would otherwise be. It's actually a contrast problem. The trouble is that grain goes up and sharpness goes down with increasing density and development. The next problem is that those wonderful black Dmax areas of the print have a tendency to bleed on sharp edges, again reducing sharpness and definition. Fortunately, when you calibrate your system you're going to pick the tonal qualities you're happy with- this whole thing is a continuum. What I call not-quite-black might be a black cat in a coal bin at midnight to the next person, or vice versa. I value shadow detail greatly and for some reason I'm very sensitive to loss of separation in the highlights of snow scenes and the like. Thus, I try to stay out of the depths of the toe and off the shoulder. Someone else might look at the same print and find no fault with it whatsoever. Shooting mostly 35mm, I don't agonize *to* much over this, since the whole roll is going to receive the same development. I do the best I can with exposure, then work on the problem areas in the darkroom!

-- Conrad Hoffman (choffman@rpa.net), April 09, 2000.


Where you place zone I depends on the amount of shadow detail and contrast you want. A denser zone I will increase shadow contrast, but as you increase exposure, grain and sharpness suffer. If you use small format, you may be more interested in grain and sharpness than in rich shadow detail.

-- William Marderness (wmarderness@hotmail.com), April 09, 2000.

When a person looks at a well made print, he is naturally drawn to the brightest parts of the image unless he's a printer obsessed with maximum black. Concentrating on maximum black goes against human visual perception. I think that if you give the film just enough exposure to get good shadow detail (uniform frame zone testing does not take flare into account) and concentrate on midtone contrast and highlight detail, it will be easier to make good looking prints.

-- Tim Brown (brownt@ase.com), April 10, 2000.

Tim

I would agree that too much emphasis is put on having maximum black somewhere, and be it only a pinpoint spot. That, of course, is nonsense. I find that a satisfactory rendition of the shadows is more important than that. Still, I guess you will also agree that a print lacking overall contrast, i.e. one where the shadows are more or less dark gray, is not satisfactory. The best contrast you can get in a print is that between max. black and paper white. The negative being capable of representing a broader range than the print, I think it's a good idea to try for max. black.

-- Thomas Wollstein (thomas_wollstein@web.de), April 11, 2000.


Sorry to be the bearer of bad news but just about any "normal" print will not have anything near a maximum black, if it does it is in trouble.

Try it, take a piece of paper out and expose it to roomlight, then develop it and place it next to what you think is max black on a normal print, you'll be suprised.

Mark.

-- Mark Bau (markbau@altavista.com), April 23, 2000.



The goal is to make a negative that you can make a good print out of.

Zone system is a way to do this under certain conditions with certain subjects.

The more important thing is to shoot a film a lot and figure out how *you* need to expose it to get a good print. Arbitrarily calibrating your film speed, exposure, and/or development to an artificial standard because the gods of photography did it that way will do you no good.

As for making prints, I proof prints at a guessed exposure that is fairly uniform for all negatives. But when I make a print for real, I test strip to get the highlights where I want, and then change the contrast to get the overall look that I want and to get the shadows to the right density. Others work differently. If you work differently, you might find my negatives really hard to print, but I've gotten good at it.

HTH, YMMV.

-- Pete Su (psu_13@yahoo.com), April 23, 2000.


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