Dumb Question on N+1 / N-1

roscoetuff

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I'm reading about the Zone system and I'm still unclear when they get into development and start talking about contrast outside the ideal of 5 zones what happens when you adjust in development. The basic is fairly clear that you're going to either lengthen or shorten the time, but where I'm unclear is whether this backs into how you expose and means that you'll re-rate your film's ISO (or similarly adjust your exposure with the shutter or aperture) at the time of shooting. The alternative is that you just shoot "as normal" and adjust ONLY with the development time.

Anyone have a clue, I'd appreciate the enlightenment. Meanwhile... back to my non-nirvana zone.
 
Either.

Reduced development = reduced contrast at any given exposure = longer tonal range captured for printing on a given grade of paper.

Then, for decent quality, you need to increase exposure because reduced development = reduced film speed. If you don't reduce development too much, increased exposure won't matter all that much, but the Zone Gospel as embraced by the Zone System Liberation Front involves making everything is difficult as possible. The People's Zone System Front takes a slightly different view.

Increase development slightly, and you get more contrast: useful for flat subjects. Or use a harder grade of paper. Similar arguments apply: more development = more speed =less exposure. Or just overdevelop slightly and don't worry about piddling about with small changes in EI.

Bear in mind, though, that the Zone System antedates variable contrast paper, let alone scanners.

Cheers,

R.
 
Me hat's off to the Python! And now for something completely different:

Keep in mind that the Zone System, so-called, was really developed for sheet film. You could customize your development for a single shot/subject. With roll film, the principles apply of course, but it is a worse fit for how folks actually shoot a roll of film. In a portrait studio, you might have control over the lighting AND the same subject over many rolls of film. However, most of my 35mm rolls have multiple subjects in multiple settings with different lighting. It is just how I work. Having said that mouthful, it is all really about having a limited dynamic range in your film -- kind of like a moving "window" of workable exposure, which you can tweak at the edges.

Your shadows are controlled by exposure, which is a fancy way of saying that if there isn't enough light striking the film you get = black (no detail). But if you try to "boost" what is in the shadows too much by developing for longer time, you can overdevelop the highlights, and no amount of shining light through those portions of film will ever get you anything other than "white." Got it?

Well if you are doing as Roger said, and trying to give a subject with deep shadows a bit more exposure, you may have to pull back a bit in your development to avoid blocking up your highlights. The "Zone System" tries to systematize this by bringing some basic sensitometery to the problem and make things more repeatable. But it is very easy to get obsessed about the tonal range and lose the forest though the trees.

So: if you have a roll of film of all one subject, or of only one subject that you are concerned about. AND you have been rigorous in your exposures of that subject and have a sense of how it differs from your default/ordinary set of conditions. AND you know that you intentionally overexposed the film and have highlights that you want to preserve. THEN pull back on your development -- test at 10% less time and see what that does for you. That is your N (normal) -1.

Conversely if you have a subject that is very high contrast and for which you want to preserve your highlights (white egg on a sheet of white paper in bright sunligtht) you can pull back on your exposure a stop and/or develop a little more (again, test at 10%). This is your N+1 and it will pull things away from >grey< towards white.

The most important thing about this is that it will depend on YOUR camera, YOUR lens, YOUR Film, YOUR Developer, YOUR water Ph and so on. So key to this is taking good notes and finding what works.

The joke of it though, once you go through the trouble of figuring your process out, you won't need a recipe for doing this (which is all the Zone System is) any more than you need a recipe for frying an egg. My bottom line advice would be not to worry about it too much unless you are regularly confronting problems in your printing and are unable to produce results you like. Or bracket your exposures, and see where that gets you.

Hope this helps.

Bat's nipples, get 'em while they're hot!
 
I read someplace, I think in one of Roger's monographs or one of his books, that modern (thin) emulsions do not work as well with the Zone System as the old 'slow and unsharp films.' I did find a hint in his passage on this subject on page 77 of Roger's "Perfect Exposure.'
 
Glad to see some other fans of "Life of Brian" here, too! Thanks for that. I'd be in favor of the People's Front for Zonal Liberation (PFZL) myself rather than that dreaded Zonal Liberation People's Org (ZoLiPo)... but of course I belong to the Confused People's Zonal Mind Meltdown.

Also, let me thank charjohncarter for some of his book recommendations a while back - probably posted to another forum denizen, but I picked up on them. Helpful.

Sounded in one of those books as though the low contrast (which is a winter, gray day thing here for sure!) is dealt with in longer development... but then it got all sketchy as to whether you were going to feed that back into the actual exposures you make. And mindful of the sheet vs. roll film thing, I've been loading 24 exposure or less 35mm cartridges just to try to shoot the whole thing at one outing. As a guy coming at this from digital, even 24 shots is like... huh? "Only!!! 24????!" so that seems to work (until it doesn't). But yes, I get that in the real world the general idea is going to be like cooking fried eggs and the principles applied without all the science - which is another way of saying I'll mess with the experimental stuff just for kicks, but I'm not planning on buying a densitometer (or whatever it is).

So am I close here? Sounds like for N+1 or N-1 you could just adjust in development as a short hand, but N+2 or N-2 you might want to do both? Or am I off track?
 
... Sounds like for N+1 or N-1 you could just adjust in development as a short hand, but N+2 or N-2 you might want to do both? Or am I off track?
That's pretty much it.

I normally overexpose slightly (because I prefer the tonality) for both long and short brightness ranges, but I may (seldom do) use what I call "15/50": 15% less development for contrasty subjects (long tonal range) and 50% more for "flat" ones (misty days, etc.)

As EVERYTHING on the roll has to be developed to the same contrast, this is (as already noted) ideal only for sheet film unless you shoot a whole roll of the same sort of thing.

Remember, too, that you can "punch up" a flat, low-contrast negative with hard paper and "tame" a contrasty negative with soft paper.

Incidentally, "blowing the highlights" is quite difficult with many emulsions, where in normal printing there's plenty of straight-line portion left above the densities you can actually print.

Cheers,

R.
 
The zone system, to greatly simplify things, is a set of procedures for testing and exposure and development designed to prevent underexposure of your negatives and over development of the same negs. The basic rule is "don't underexpose, don't overdevelop", and here's a pile of books to teach you how to follow that basic rule.
 
Roger's exposure system is very similar to the one I worked out for myself in the early 1970s when I changed from MF (mostly Rolleiflex) to a Nikkormat and found the camera's meter was constantly exposing from the center of the image. Until then I had used a Weston Master which tended to average out the entire exposure and gave me more consistent results.

After a bit of trial and error testing I worked out my own system, based on the KISS principle. For important images, I shot two negatives, the first one third of a stop over and the second one third of a stop under the metered exposure.

Back home in the darkroom, in 95% of my film processing was for normal times. I used D76 1+1, the Thornton Two Bath Ansel Adams mix (sorry, Roger!) and Xtol, the latter to replace HC110 after Kodak stopped selling it in Australia.

An interesting point with my KISS system is that when I try out new films, my processing for the manufacturer's normal times always give e consistently good results, without the need for much testing beyond shooting usually no more than one test rolls. My images scan beautifully and I can easily make prints without having to resort to three ring circus acts of dodging and burning in. Which suits me well as I am basically a lazy photographer anyway.

As always, there is much useful information in this thread and I have learned a lot from reading it. Thank you all, and especially Roger who has so much experience and has written about these matters for many years in his books and OL.
 
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