Question about Zone

[Bill Burk]

I've put together a spreadsheet that determines the aim contrast index from the subject luminance range and paper LER for a diffusion enlarger. This is based on my practical development model as described in my paper "What is Normal?" The resolution is poor. The file is the largest this site will allow.

Attachment 127897

Thanks Stephen,

I will adopt this chart, and will refer to it often when giving advice to develop to contrast. It's a refinement of the chart you gave me last year which served well... this one's even better.

[Stephen Benskin]

Not sure if anybody has had the chance to look over the spreadsheet, but by you can also see what grade of paper a "normally" developed negative will need to print on depending on the subject luminance range. Pick a CI for normal conditions. I use the statistical normal LSLR 2.20 - CI 0.58. Next look where 0.58 occurs under different LSLRs. For example, there's a 0.58 at a LSLR of 4 2/3. For this subject, the matching LER is grade 4 1/2. This, of course, doesn't account for aesthetic decisions.

[kintatsu]

Ansel Adams himself said that The Zone System wasn't set in stone. He explained it as an aid in visualizing and achieving your desired image.

Using his recommendation for a Z I density of .1 and a Z VIII density of 1.3, I've been quite satisfied. My testing wasn't thorough enough, as I used my meter as opposed to a densitometer, and only tested those 2 zones.

Again, though, I'm happy to use it as a great guide to getting what I see onto the film and then the paper the way I want.

[Drew Wiley]

I'm probably as proficient as anyone when it comes to Zone theory, and I never even think about it anymore, either when shooting or in the darkroom. After awhile you just get a feel for what you're doing. In any event, every single combination of film, developer, and subject is a little different problem, then this all gets replicated in the darkroom when in comes to potential variables. And I work with all kinds of combinations. You can go crazy thinking about this stuff, or you can just do it and not get hung up. Therefore I regard the Zone System as a nice introductory learning tool, with a lot of nice literature behind it, but otherwise, consider that making a religion out of it is absurd. Like many other things, you can make it either as simple or as complicated as you choose. But change one variable, and everything else has to be altered too if you draw out this kind of concept to its logical end. ... And I do know how to use a densitometer, but haven't needed it for general photography ever, just for fussy lab projects like color masking and color separations.

[Robert Bowring]

Mr.Wiley is correct. Could not have said it any better. Do not drive yourself crazy about this stuff. It sounds like you have done enough testing to determine your approximate EI and development time. Go out and take some pictures and make some prints. Then you can fine tune your technique. The zone system is just a guide. It is not written in stone. The important thing is to get the results that work for you.

[Argentum]

The proof of the pudding is in the eating and with that in mind forget about all the numbers and do some eating by way of reproducing the zone patches in Chapter 4, figure 4-3.

When you can photograph a piece of hardboard (without the light changing) so that you have 11 negatives which when all printed using the same time, produce that series of patches with nicely spaced print values then you know you have nailed your film speed and standard development time.

The only thing I would suggest is that when finding the time to use to print them all, is to work it out using the zone 1 negative (NOT zone 5 negative) to produce a test strip and find the first strip which is just perceptibly lighter than max black(which is never as black as the paper can go if you over print it). And print on paper without any filtration.

Then when you've achieved that you will have learnt a lot of practical procedures and if you must, you can measure the densities of each zone negative and have your answer. What you'll do with the numbers I have no idea except maybe waste some time making graphs instead of prints.

Things you should know:

ISO standard is designed for approx 8 stops from black to white. When you calibrate for 10 stops from black to white that will require approx 1 stop slower film speed than ISO speed (extra exposure) and approx 30% to 50% less development than manufacturers recommended times. These things are very varibale depending on film, dev, paper, paper dev and your working procedures in general so its important that you use consistent process for repeatable results.

And finally a kodak 18% reflectance gray card is NOT the middle of a 10 stop range when measured with a light meter but thats another story.