Zone system - how to understand it?

[bob01721]

"... I believe the difference between the idea of the 21 step and ~7 stops is that one is for sensitometric purposes and the other for tone reproduction. The Zone System uses the seven stops for Normal because that is the average luminance range for scenes..."

Steve, Ron... could (would) either of you elaborate here? My experience with the ZS literature is an eleven stop range—zero through 10—not 21 or seven or...

What have I missed?

 

[Allen Friday]

I have read the Adams book and the Picker book. For my money, "The Practical Zone System" by Johnson, is head and shoulders above either one when it comes to an easy to understand, straight forward explanation of the ZS. The Picker book is good as far as it goes, but it ends with normal development. It does not go into plus or minus develpment and metering of scenes requiring other than N develpment at all.

Allen

 

[Stephen Benskin]

Steve, Ron... could (would) either of you elaborate here? My experience with the ZS literature is an eleven stop range—zero through 10—not 21 or seven or...

What have I missed?

This is where the ZS really falls short and I feel leads to much confusion. I believe Adams came up with the O - X range for paper based on the Munsell scale. He then tried to shoe horn it into scene luminance, but the range for his testing procedures says something else. Adams range for testing I - VIII is seven stops, so the range for calibrating your development closely corresponds to tone reproduction theory. Without going into the discrepancy of his density range to the tone reproduction density range, normal processing for both ZS and tone reproduction is approx. CI 0.58.

Others on this forum know Davis' version better than I, but I believe he attempts to solve the discrepancy between a ten Zone paper scale and a shorter scene luminance range. I personally think he makes a valiant effort to make the faulty original ZS concept work.

 

[Photo Engineer]

Steve;

No doubt you are right, I was just trying to inject a little levity into it. Read my post again regarding 'music'...

Anyhow, the situation is as you describe and the 21 step chart is the effort of engineers to get more detail.

The intent of Adams and others was to try to contain the usable range of the zones to the center straight line portion of the curve, because, as you say, it is the normal luminance range and also is the best part of the negative.

If you slide the 7 zones downward to the toe or upward to the shoulder, then you get compression of data and have to 'uncompress' the data by adjusting development time accordingly.

PE

 

[bob01721]

Whew! And all this time I thought I understood the Zone System! Ha! Now I find there are several more layers.

Makes me dizzy just to think of it!

 

[Stephen Benskin]

Whew! And all this time I thought I understood the Zone System! Ha! Now I find there are several more layers.

Makes me dizzy just to think of it!

The ZS is for one a good tool for visualization, two a simplification of tone reproduction theory, and three flawed.

 

[Donald Miller]

Steve,
I concur...

 

[JBrunner]

If the original poster of this thread is trying to apply the zone system to the "format" I believe he is really interested in, well, your talking about maybe three stops of real latitude and an abrupt shoulder and toe, so a pretty tough row to hoe. It is designed with much more in mind than that "format" can deliver.

 

[Helen B]

Rhys,

Are you using colour or B&W film? Do you develop your own film or send it to a lab?

The Zone System is only one approach towards getting the exposure you want. There are other ways of getting there, each with their own purpose.

There isn't really any such thing as a universally correct exposure, but there is the correct exposure for what the individual photographer wants.

One fairly standard exercise when you are starting in photography (and when you are learning a new film or even a digital camera) is to do a series of different exposures of the same scene, noting how the exposure relates to the meter reading, and what you are metering off. Then try to make the best print from each of those frames. See how the tonal relationships change, see which print you prefer, see which part of the tonal range is most important to you.

You may wish to peg your exposure to the midtones, you may wish to peg it to the highlights. You don't have to peg it to the shadows. I'd forget about trying to apply the Zone System to begin with, though there is no harm in reading and, more importantly, understanding texts about it.

Best,
Helen

 

[bob01721]

The ZS is for one a good tool for visualization, two a simplification of tone reproduction theory, and three flawed.

Well said. I use it mainly to visualize a printed image. As long as I know my shadows will show detail and my highlights aren't blown out too badly, I'm happy. Beyond that, I don't get too technical.

 

[rhys]

Rhys,

Are you using colour or B&W film? Do you develop your own film or send it to a lab?

The Zone System is only one approach towards getting the exposure you want. There are other ways of getting there, each with their own purpose.

There isn't really any such thing as a universally correct exposure, but there is the correct exposure for what the individual photographer wants.

One fairly standard exercise when you are starting in photography (and when you are learning a new film or even a digital camera) is to do a series of different exposures of the same scene, noting how the exposure relates to the meter reading, and what you are metering off. Then try to make the best print from each of those frames. See how the tonal relationships change, see which print you prefer, see which part of the tonal range is most important to you.

You may wish to peg your exposure to the midtones, you may wish to peg it to the highlights. You don't have to peg it to the shadows. I'd forget about trying to apply the Zone System to begin with, though there is no harm in reading and, more importantly, understanding texts about it.

Best,
Helen

Actually, I do all of the above. I develop and print my own B/W films, shoot slide film, shoot colour negative (I do develop my own slide film and used to develop my own colour negative and do the colour printing too but these days I tend not to since labs are so cheap). I also shoot digital. Actually, the only processes I don't do are E4 and C21.