Negative density in zone system

[sergio caetano]

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

 

[Doremus Scudder]

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

 

[sergio caetano]

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

 

[DREW WILEY]

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.

 

[Bill Burk]

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

 

[RalphLambrecht]

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

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.

 

[Bill Burk]

Thanks Ralph,
Your chart is helpful.