Negative density in zone system

Dear fellows (2 questions)
1. Zone System Manual . Zakia et alia page 134 : Negative densities correlated with zones differ based on film formats . I cannot understand why they can be different. Ex.: Zone V - 0.75;0.70;0.65 - 4x5;120;35mm respectively. I have always thought that density is density,and it could not vary in function of film formats.
2. Controls in BW . Richard Henry 2nd edition page 76 ; Film developed to CI 0.41 had a film D of 0.57 for zone V, and with CI 0.57 film had a film D of 0.84 for zone V. I have always thought that only film D 0.75 could result in print RD 0.75 (zone V).
Where am I wrong ?
TKS

Sergio,

Minor White, Zakia, Ansel Adams and other Zone System proponents advocated tailoring smaller-format negatives for a higher-contrast paper (grade 3 in those days) in order to reduce overall C.I. and, thereby, graininess a bit. Large-format negatives could stand a greater C.I. without the grain becoming a problem.

As far as which density equals Zone V on the paper: Theoretically, any negative density can be printed at a middle gray on the paper equal to Zone V. It's just a matter of exposure. One could even flash paper without a negative to a Zone V density.

When using N+ or contrast-expanding development schemes, the overall C.I. increases proportionally from the low densities to the higher ones. So, even middle density values will be affected. If, for example, N+2 moves a metered Zone VI up to a Zone VIII negative density, then Zone V will move almost two Zones as well. Zone III will move about one Zone higher, etc., etc.

The density range between low and high values on the negative together with paper contrast is what determines the overall density (contrast) range of the print. Even negatives overexposed by two or three stops, but developed so the density range between Zone III and Zone VIII is "Normal," will yield a normal-contrast print on the target contrast (grade 2 usually) paper.

Does all that make sense?

Doremus

Doremus
First of all thank you so much for your quick and consistent response.
For sure zone V printing may depend on exposure, but I still think that a "normal" negative, with zones correctly put (as previsualized), taking care of middle tones (mainly III to VII textured zones), developing for CI 0.56, printing in my Omega D2 with diffuse light etc, zone V density (pivot point) will make all others dependent, each one with its "normal" density, otherwise (searching zone V not by std printing exposure) I would be corrupting (displacing) the other zones.
Obs.: This does not mean that I always get these optimum results.
Best regards
Sergio

Different films can have different fbf's (film base plus fog). That amount has to be subtracted from the image density as measured with a densitometer. 120 roll film in particular has a relatively high base density due to the more stringent antihalation layer necessary for daylight loading. I've seen sheet film with "clear" margin readings of anywhere from .04 density to around .20, depending on the specific type. Even different brands of 35mm film can vary somewhat. Then if you use a staining pyro developer, you have to factor that too.

Otherwise, there are all kinds of additional factors which can unnecessarily complicate this whole topic. The Zone System can be a maze unless you realize the shoe is supposed to fit your own foot, and not the other way around. It's proponents and gurus seem to think in a one size fits all mentality - namely their own shoe size. Even the number of "Zones" can be customized to one's own needs and linear range of the specific film itself.

Often a simple test strip will tell you far more about being on the right track or not than reading endless quantified articles.

The New Zone System Manual explicitly states 0.10 above film base+fog for Zone 0 then jumps to 0.33 for Zone I 35mm

I think there’s a couple things wrong. 0.10 is supposed to be for Zone I

And I think they didn’t zero on base+fog.

So there may need to be an audit to correct their chart. I don’t think it’s right.

Ansel Adams offers corresponding recommendations on page 220 of The Negative. His numbers have been generally accepted

sergio caetano said:

Dear fellows (2 questions)
1. Zone System Manual . Zakia et alia page 134 : Negative densities correlated with zones differ based on film formats . I cannot understand why they can be different. Ex.: Zone V - 0.75;0.70;0.65 - 4x5;120;35mm respectively. I have always thought that density is density,and it could not vary in function of film formats.
2. Controls in BW . Richard Henry 2nd edition page 76 ; Film developed to CI 0.41 had a film D of 0.57 for zone V, and with CI 0.57 film had a film D of 0.84 for zone V. I have always thought that only film D 0.75 could result in print RD 0.75 (zone V).
Where am I wrong ?
TKS

Click to expand...

I don't think you're wrong at all. film density is not a function of film stockbut a function of exposure. Attached are the densities I shoot for.

Thanks Ralph,
Your chart is helpful.

Zone V "middle gray" is not really a set point in the Zone System at all. The real data points are the minimum and maximum densities that print with texture when the fb-fog area of the negative prints at, or very close to, maximum paper black. This is the gist of The New Zone System Manual's visual method (i.e., sans densitometer) of ZS calibrations. Of course all this is dependent on the contrast (and curve shape) of the paper chosen for testing.

In practice, then, the whole calibration of a particular film, particular paper and particular photographer's metering technique and equipment. This means that the actual negative densities for any given Zone will vary somewhat depending on all these variables. And, it doesn't even take into account that overexposure will boost the density range between Zones III and VIII while still providing a negative that is capable of producing an excellent print on the target "normal contrast" paper.

Starting from an average Zone V density and expecting everything else to fall into place if you simply develop to a recommended C.I. seems like an exercise in futility to me.

Best,

Doremus

So much absurdity when generalizations are being imposed, and the curve shape of the specific film itself isn't taken into account. Not all films are the same in terms of shadow gradation!