Mortensen and Gradation

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William Mortensen was a pictorialist with an unusual take on how film should be processed. I have a lengthy article about his 7-derivitive technique at http://unblinkingeye.com/Articles/Mortensen/mortensen.html

Whatever one may think about the aesthetics of his photographs or the controversy over pictorialist versus "straight" photography, there is no doubt that Mortensen was an accomplished darkroom worker whose views cannot be dismissed out of hand. His most significant assertion is that expanding a short-scale subject gives more pleasing gradation than compressing a long-scale subject. Coming from Texas, I almost always encounter the latter situation. My few experiments with Mortensen's technique gave mixed results, but the successes I had were definitely worth the trouble.

I'd be curious to hear the opinions of the contributors to this forum on the subject. Have you ever noticed better gradation from expanding scales than from compressing them? If you don't know anything about Mortensen, take a bit of time to educate yourself. Read my article for the technical stuff, then check out the links at the bottom of the page to see some of his photographs and read other opinions.

-- Ed Buffaloe (edb@unblinkingeye.com), July 09, 2001

Answers

I suspect this might well be the case - its probably related to the local contrast issue David Kachel railed about in his articles in DCCT. I suspect it is fairly common to have perfectly tailored negs which are them printed on higher contrast paper to ensure sufficient local contrast in some key area (followed by the necessary heroic dodging and burning) - the simplest example is how doing an N- leads to somewhat murkier shadows but there probably are more complicated situations.

Expanding a limited scale subject ensures good local contrast throughout the image. However, I think this is something that is worth being careful with these days. I guess these are personal decisions but I see many pictures with overly harsh local contrast - they are very dramatic but seem to lack subtlety to my eye. Papers have improved substantially from the old days (in terms of Dmax). This means that papers probably can hold more information and expanding limited scaled subjects onto such papers can make for enough distortion of reality that I think one needs to be exercise considerable sensitivity to the subject and image.

Its not much help in the more complicated situations when one needs to hold a longer subject luminance range and yet ensure sufficient local contrast in some part of the image - I find those kinds of subjects troublesome in the extreme (sort of broad level controls during neg development but more often than not demanding in the printing stages). One could find ways that work for a particular kind of photography - for e.g., the typical landscape concern of ensuring sufficient detail (local contrast) in the shadows while holding a longer range lends itself to some overexposure coupled with some kind of compensating technique.

I think there is another issue here beyond local contrast and that is related to how film and paper work together. One will often hear people talk about platinum's longer scale etc. However, actually, silver gelatin papers typically have considerably higher Dmax than platinum papers. Which means that they should have a longer scale. The problem is that the silver enlarging process relies on a low contrast (gamma or slope of HD curve) negative combined with a high contrast paper (as opposed to platinum - you seem to develop to about slopes of 45 degrees or thereabouts - sort of a 1:1 relationship). That means there is considerably more accuracy required in the silver development process, minor changes in the curve shape can have dramatic influences on the final print. Also, typically development slows down as it proceeds (an overgeneralization but some grain of truth to it) i.e., the early stages of development are very sensitive to minor variations. Expanding scales implicitly means developing to a higher CI and therefore ending up in the more stable region (I'm curious, which negative do people typically have trouble printing - N+ or N- : for me, typically the N+ print with no trouble at all). I think that is because there is less compression/expansion going on in each stage.

Cheers, DJ.

-- N Dhananjay (ndhanu@umich.edu), July 09, 2001.


I have found that when needing to do minus development, I use the middle of the film curve to take advantage of the linear separation of values. If you use the lower end of the curve, you end up with muddy shadows. Compression happens in the shadow values first so you have to compensate by moving the shadows way up the curve. Then when you compress you compress most of the image linearly. The dodge, and reburn the shadows with a higher filter. James

-- james (james_mickelson@hotmail.com), July 09, 2001.

Hi Ed.
I must admit, I haven't read the Mortensen article yet, so these are just some immediate thoughts on the subject of development manipulation:
I decided a long time ago that pulling development wasn't a good idea, for the very reason that it gives flat muddy negs that can be quite difficult to print. Besides, messing about with development too much alters the relationship of tones in the negative relative to the way that the subject is actually seen, and therefore makes that precious and elusive pre-visualisation much more difficult.
It's all very well squeezing every nuance of subject detail into a printable range on the negative; but if the result just looks grey, and the desired atmosphere of the picture isn't conveyed, then vision becomes a slave to technique, and not as it should be, the other way round.

Using the curves tool in Photoshop on scanned images has recently given me a much better feel for, and insight into, which sorts of tonal adjustment look good, and which don't. IMHO, a long straight tone curve is undesirable, and the only way to deal with a wide brightness range is to 'bend' the top and bottom of the transfer characteristic.
If at all possible, the mid tone gamma should be kept fairly constant, and the shadows and highlights rearranged around it. In other words, a compensating developer technique gives a better looking negative than simply pulling a normal development.
(Flush that T-max developer now!)

-- Pete Andrews (p.l.andrews@bham.ac.uk), July 10, 2001.


This is really interesting. I'd seen Mortensen's stuff, but never knew anything about his processing theories. Pete probably said better and in fewer words what I've been thinking lately, that pulling often doesn't work well, and that a long straight film curve is undesirable. Actually the best curves for tonal reproduction were established way back by Kodak and RIT- see Photographic Sensitometry by Todd & Zakia. Think S shaped. The problem is that modern materials seem to be optimized for a straight line. Even paper seems to be more linear than it used to be. Film Dmax seems lower than it used to be and whenever I cut film development, rather than a nice shoulder, it's more like a sudden shelf. Doesn't help latitude any. Some of the nicest negs I ever shot were on Ektapan, a long toe film with no super straight line. It's still listed in the catalog, but I wasn't able to get it recently.

-- Conrad Hoffman (choffman@rpa.net), July 10, 2001.

I have never really had any problems with small normal minus dev.. I always use a highly diluted dev. for extreme cases, and haven't had any objectionable mid tones with that process.

I'll flush the tmax only after I have made some grand looking negs! :)

-- mark lindsey (lindseygraves@msn.com), July 10, 2001.



"I always use a highly diluted dev. for extreme cases,"
Isn't that exactly what compensating development is?

-- Pete Andrews (p.l.andrews@bham.ac.uk), July 11, 2001.

To answer my own question, most of my experiences with N-minus development have been negative (if you will pardon the pun). However, I met a fellow, Butch Welch, at APIS (the Alternative Process International Symposium) who uses diluted T-Max RS to develop his long scale negatives and gets superb results. Butch says the film is part of the secret--you must have a film that retains it's straight- line and does not shoulder off when development is reduced. His choice is T-Max 400. He claims you can't do it effectively with any of the Ilford films. In any case, I asked him to write an article on his technique for publication on Unblinking Eye, and he is considering it. I would also point out that Bruce Barnbaum has been quite successful with N-minus processing--witness his cathedral photographs and some of his slot canyon shots. He uses diluted HC-110 and Tri-X. Of course, that still doesn't address the (possibly subjective) issue of whether N-Plus or N-Minus is more aesthetically pleasing...

-- Ed Buffaloe (edb@unblinkingeye.com), July 20, 2001.

> can't do it effectively with any of the Ilford films

Interesting...I've always had the devil of a time putting a usable shoulder into HP5+ and Delta 100 while maintaining enough agitation for good evenness. The curve shape is always dead straight out to Zone XII+.

The only success I've had has been with D-23 or D-25 using dramatically shortened development time, followed by a bath in borax solution. To me that's rarely-used "heroic measures" and always results in muddy low-contrast highlights; otoh I often can't decide which is worse, low-contrast highlights or _lots_ of burning-in.

-- John Hicks (jbh@magicnet.net), July 20, 2001.


That sounds interesting. I don't know if it solves all problems because we have something of a basic problem with N- developments. Eventually, when we deal with extremely long luminance ranges, the paper is unable to accomodate the entire luminance range. Thus, our attempts at all kinds of measures to try and get the neg to print 'normally', whatever that is. But the problem is that if you have a luminance range longer than the papers luminance range, its problematic. Note I'm not talking about the exposure scale of the paper - I'm talking about Dmin to Dmax of the paper - if we say about 2.1 density units, thats about 7 stops. If your subject luminance range is more than 7 stops, you will lose something at one end or the other. So, we try various measures to try and get everything in, but that raises the other bugbear. The only way we can accomodate a longer subject luminance range with the paper is by reducing the local contrast in some area or the other (lower slope to the transfer function). Depending on the approach taken, typically we either get muddy highlights or muddy shadows. If one is able to drop the slope of the curve uniformly, one presumably loses local contrast uniformly across the whole scale, although I think that's preferable to losing an excessive amount at one end. DJ

-- N Dhananjay (ndhanu@umich.edu), July 22, 2001.

> If one is able to drop the slope of the curve uniformly, one presumably loses local contrast uniformly across the whole scale

Yes, I've found that generally I prefer that solution. The only time I go for the "heroic measures" of putting a strong shoulder into the film is when I'm faced with background very bright sky through the trees. The range between foreground subject and the bright sky is so great that there's no way to hold both so it's preferable to be able to print at least a slight tone in the sky rather than blank white that can't reasonably be burned in.

It gives a weird curve shape, with pretty much normal contrast up to about seven stops, then almost flat. I'd call this extreme compensation but since there's so little contrast up on the high end there's no printable detail.

In looking at photos of similar subjects by other photographers, I've noticed that they generally handle it by not handling it; they either frame so there's virtually no background sky visible or they just let it blow out.

-- John Hicks (jbh@magicnet.net), July 22, 2001.



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