Zone system film development/exposure

As a relative newcomer to zone system control of exposure & development I've tried, rather incompletely, to understand the strong emphasis placed on making negatives that will have a range of values supporting the visualized result, printed on "normal" grade paper.

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In particular, I see repeated caution against an approach that ensures all imporant values are contained in the negative, with final contrast control left to selection of paper grades. This form of approach, I've repeatedly read, (without satisfactory explanation) is inferior to manipulating contrast in the negative development stage.

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Why is this so? In fact, in my limited experience, it may be better to resist expansion development of the negative, for example, in order to control grain. Normal development with expanded contrast in paper grade selection can produce equally compelling results, no?

Your theory may result in printing problems. If you try to integrate

expansion into the image through contrast filters, you lose tonality.

As one moves to higher and higher contrast filters, the higher values

approach white, the darker values approach black. Thus important

detail at the Zone Vii/VIII areas and at the III/IV areas may be

compromised. Split filtering approaches may reduce this tendency

somewhat, but not completely and not enough. Expansion to N + 1 or

thereabouts, the use of Selenium Toner for increased expansion does

not reduce one's abaility to transform the information on the

negative to the papser.

By the same token, compression of development gives the printer more

to work with than does the use of softer filters or lower grade

papers.

Others more familiar with zone system curves can probably better

answer your question. But, in a word, you get better results. After

seeing my first 4x5 photo developed 25 years ago using the zone

system, I immediately tried to replicate that same result by varying

enlarger exposure and paper contrast. It wasn't possible. While I

could maintain the highlights, the dark areas weren't right. The

information simply was not in the negative. It wasn't until I learned

and applied the basic zone system tenet of exposing for shadows and

developing for highlights that I was able to achieve the result with

which I had been so impressed. Even now, I see photographs with poor

contrast control, and I think: Nice photo. Poor execution. Too bad.

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So, I have my own tenet that it's best to make "adjustments" as close

to the object of the photograph as possible. Better to change

lighting than add filtration. Better to change the filter than effect

color correction in the darkroom. Etc. Since it's not possible to

adjust lighting in a scenic photo, it's better to adapt the negative

to the constrast in the scene, versus attempting to adapt the paper to

a poorly exposed and developed negative.

In large format, grain is not a great worry. Printing on a normal

grade paper gives you much greater latitude for print manipulation

and control of gradation. Printing on higher contrast grades narrows

your range of correct exposure and can limit further manipulation

(though modern VC papers help a lot with this problem). I have plenty

of old negatives that contain 12 to 14 stops of information, but I

can only print maybe 8, if I do a lot of dodging and burning and stay

in the darkroom for hours. I think most Zone System pros manipulate

their negatives, then manipulate the prints too--they're just trying

to give themselves as much room as possible for creative control. I

recommend you investigate staining developers such as W2D2 pyro, PMK

pyro, Pyrocat-HD, and Dixactol, as they really do seem to allow you

to capture a greater printable range on your negatives.

Printing a high-contrast negative on a low-contrast negative give

better tonality. Platinum prints are praised for the detail they hold,

and this process involves very high-contrast negatives printed on very

low-contrast negatives. A. Adams mentions in The Negative that

developing negatives to print well on a grade #1 paper would be

produce better gradation than producing normal negatives for grade #2

paper. He suggests that grade #2 paper be the target because it allows

one to print on grade #1 if needed. With grade #1 as the target, there

is no lower paper grade to turn to if needed. I have heard of some

photographers who develop their negatives to print on grade #1.

Please excuse my mistakes in the above post. I wanted to talk about

printing high-contrast negatives on low-contrast papers (not negatives).

Having a wide range of contrast papers/filters at your disposal is an

excelllent means of expression. However, the higher contrast grades

can turn print making into a real chore. You think your neg. is

clean? Printing it with #4 contrast will change your mind. Then, plan

to spend some quality time with your spotting brush... Not to mention

the time spent making the print in the first place. With #2 contrast,

a 10% dodge will produce a barely perceptible change; With #4, it's

like night and day. Getting it right can be be a very expensive

proposition.

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All things considered, it's best to start visualizing with the neg.

I'll open a bag of worms here but my target is to make a negative that

will just barely fit on a #2 paper sometimes with a pre exposure burst

because when achieved I believe that has opened the door to some of

the most beautiful gallery type fiber based papers. Those negs when

developed with pyro will print about as well in Pt/Pd as on a longish

fiber #2. I'd hate to be limited to Ilford Multigrade Rapid and a #3½

filter for a fine art print. So there's at least one guys

reasoning.

Ernie, This is a good question and has no really simple answer. The

most important thing the Zone System does for us is to make sure we

don't have to deal with negatives that are way too contrasty or way

too soft to satisfactorily print. I agree that, for most negatives,

tailoring for a grade 2 paper will give the best results. However,

with all due respect to the above contributors, there are instances

when tailoring a negative to print on grade 3 (or higher) paper

results in a better print. The first, and most obvious of these

instances is where small negatives are used and grain is a factor.

Even Ansel Adams recommendes tailoring smaller negatives for grade 3

paper to reduce grain. The second instance is when an expansion of

local contrast is important to the image to be printed. Since a

higher contrast paper separates close values better than expanded

development, it is sometimes advantageous NOT to expand some

negatives fully by development, but develop them to a point one paper

grade under "Normal" and print them on the next higher grade. Among

these negatives, although at first it seems counter-intuitive, are

all contraction negatives (i.e. all N- developments). Contraction

negatives tailored for grade 3 paper and given sufficient exposure to

hold the shadow details result in prints with better separation in

the mid and shadow tones; exactly the places where separation is

normally lost when these same negs are tailored for and printed on

grade 2 paper. Of course, these are refinements and modifications of

a system of exposure and development that is time-tested and

reliable. Part of the reason for choosing "Normal" grade paper for

most negatives is, as mentioned above, to give one more leeway in

printing. The Zone System is not rocket science, and there are many

variables that can affect the final contrast of negatives. If

negatives are tailored for a contrast grade that is on an extreme end

of the spectrum, then there is no go if the negative is too soft or

too hard. Possibly more important is that the curve of lower contrast

papers suit the majority of subjects better, rendering subtle

highlight separation and retaining good shadow detail which

contrastier papers do not do as well. Note however, that this is an

aesthetic consideration and that some subjects print better on higher

contrast papers (as mentioned above). The main thing that one needs

to insure is that there is adequate exposure to achieve the desired

separation and detail in the shadows, and that the negative is

developed to a point that it fits the printing paper desired, whether

it be grade 2 or 3. Simply overexposing and overdeveloping results in

a lot of negs that cannot be printed on any available grade of paper,

and, if you are interested in grain, the minimum exposure to render

the shadows as you want them is best. As one becomes more familiar

with materials and gains experience exposing, departures from

the "Normal" are used for expressive purposes. Sorry for the long-

winded repy. Hope this helps. ;^D)

There are some valid reasons to aim neg development at about grade 2.

But leaving that aside for just a moment, you raise a good point. In

fact, when Kodak first introduced different grades of paper, it was

for the purpose of dealing with errors in development. Try a simple

exercise. Assume for the sake of simplicity, that all our transfer

functions (film curves and paper curves) are linear - I know they are

not actually linear but let's start there. Pick a subject luminance

range and try plotting them on a tone reproduction cycle. You will

find that as long as you pick matched slopes for the film and paper

curves (i.e., low slope film with high slope paper and vice versa),

your final tone reproduction will be identical.

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Now, in actuality, films and papers have toes and shoulders and that

does change the tonal gradations. Also, many of the points made

earlier are absolutely valid. Working with higher contrast papers is

a pain in the neck. Burning and dodging is hideous, grain tends to be

exaggerated by the higher local contrast and as you approach high and

low contrast, you have less wiggle room, which is another reason one

might not want to aim neg development towards #2.

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But I've often thought that the best system would be to minimize the

toes and shoulder areas of the curves - that would give us the

longest possible straight line section with clean gradation - no

tonal distortions. The reason platinum looks so good is exactly for

this reason. Platinum actually has a lower Dmax but the neg is

developed to a higher CI and the paper accomodates such a neg. The

reason it looks good is because in the overall transfer function,

most of the function is a straight line - the toe and shoulder have

been reduced as much as possible. Most of the overall transfer

function is pretty close to a straight line. (And no, an

appropriately scaled neg on a silver print will not look the same

becuase the silver system will have longer toe and shoulder areas).

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The best way that can be done is to develop towards a 45 degree

transfer function. Any variation from this will tend to increase the

toe and shoulder areas of the overall transfer function (note that

this would not happen with straight line transfer functions, its a

problem only when we have curves with toes and shoulders). Typical

procedures these days for negs is to develop to a CI of about 0.5 or

thereabouts, considerably less than the 45 degree line I referred to.

Typically one is likely to get better results in the midtones if one

aimed for a higher CI - that is, a neg aimed at grade 1 is likely to

yield somewhat cleaner midtone gradation. However, that leaves you

with no wiggle room. Any errors and you are sunk.

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One reason so many folks like the way Azo looks, I suspect, is

because the final result has long straight line characteristics. That

reduces the distortions due to toe and shoulder - my subjective

opinion is that a neg aimed at Azo can be developed slightly longer

than one aimed at an enlarging paper. All of this is further

complicated by the fact that different manufacturers adopt different

methods of accomodating unruly negs. Some papers vary mainly in the

shape of the toes and shoulders. Others vary the slope of the

straight line section also. So given all of these complications and

associated problems alluded to by others, its probably preferable to

aim at the middle of that scale. Cheers, DJ.

Sorry for the typo at the end of my second paragraph - those are

reasons to 'aim at grade 2', not to 'not aim development at grade 2'.

DJ

Thankyou all so much for your thoughtful responses. This is a

fantastic site and without question, the contributions are

more informed than any other net based resource.