Understanding the zone system.

[Grandpa Ron]

I understand why Ansel Adams and others used the zone system to determine the the number of f stops the film would require to encompass the exposer latitude of the object being photographed.

However, if the subject of the photograph is what you want to show, why wouldn't you just take the exposure reading from subject?

 

[smoke665]

You say you understand the zone system but your question says maybe not. The zone system with its 11 tonal values represents "all" the values in an image from true black to true white. Each zone is exactly one stop different from the zone on either side. Camera meters and exposure meters read tonal black/white and are calibrated to render a diffused exposure value for zone
V (18% gray) reflective. So if you meter a piece of white paper and adjust your exposure setting to zero the meter. Your image will be gray not white. To get true white you'll need plus exposure compensation.

Understanding the relationship of the zones is the basis for Dean Collins Chromazone system. As all images are recorded reflective light, his system relies on the numerical zone values to control the contrast levels between the subject and background. A difference of 21/3 plus stops reflective between the background and the subject will render an 18% gray background pure white. A difference of 41/3 negative will produce pure black.

 

[Ysarex]

I understand why Ansel Adams and others used the zone system to determine the the number of f stops the film would require to encompass the exposer latitude of the object being photographed.

However, if the subject of the photograph is what you want to show, why wouldn't you just take the exposure reading from subject?

Because the context in which you find the subject may be very important and has to be included in a final exposure determination. Here's a snapshot I took in the park. Tower Grove Park in St. Louis is modeled on an English Victorian park and includes the fountain and fake ruins you see here -- arguably the subject of the photo.

In the illustration below you see first the JPEG the camera created in response to the exposure I set for this scene. To take the photo I applied a +.7 EC to the camera's meter reading. The subject is underexposed -- by a lot -- and yet the brightest highlights in the clouds are blown.

In the second image below I had the camera software recreate the JPEG but with an additional +2.3 EC for a total of +3 EC over the camera meter reading. In the second image the subject is well exposed, but the sky is totally nuked.

So how do you meter a subject and scene like this to determine the exposure. You started off with a comment about the Zone System which would be applicable to film photography. The Zone System was created to address problems similar to the one here. The foundation of the Zone System is the fact that film's response to exposure and development is disproportional and can be manipulated to a degree via development.

Film has an exposure/development sweet spot. When the scene subject and lighting contrast is a good match then a normal film exposure and development will produce a best possible tone response. Unfortunately scene subject and lighting contrast isn't always cooperative and that's where Adams and Archer stepped in with the Zone System as a means to manipulate the film tone response to be a better fit to the outlier subject/lighting contrast conditions. It is as such a manipulation applied to address a problem and comes with some degree of compromise such that the best possible tone response delivered by the film's sweet spot exposure and processing will take a hit.

If keeping the clouds and sky is important to this photo then the Zone System photographer starts taking discreet measurements to determine the overall tonal contrast of the scene. From that calculation the Zone System photographer would compute the needed reduction in film development time to reduce the contrast response of the film and so better match the high contrast of the scene. In very low contrast scenes increased development times become indicated. How to meter the subject is derived from the calculations of the overall scene contrast and where in the film's tone response the photographer wishes specific detail in the scene to be recorded. At this point in the process the brightness and contrast of the specific subject (eg. human face) factors in but is not the single determinant as the brightest highlights and shadows are also factors.

The photo here was taken with a digital camera and as such the Zone System does not apply. Digital sensors record data linearly and so that foundation fact that makes the Zone System possible (film's response to exposure and development being disproportional) isn't operative for digital.

Digital cameras all create SOOC JPEGs that are designed to emulate the behavior of film and it's possible to work with those camera JPEGs and set exposure based on those JPEGs: "pretend" you're exposing film. In this case exposing for the specific subject would be a possible and very likely best option approach since there's not a lot of latitude in a SOOC JPEG for further adjustment. If shooting camera JPEGs, set an exposure that's ideal for what you've identified as the subject of the photo. If trying to do that you encounter very high or very low subject/lighting contrast conditions the Zone System isn't built into the camera picture controls and you have to make do with what the camera provides. In the case of the above photo my Nikon provides a function Nikon calls ADL (Active D-Lighting) to address very high contrast lighting. In the scene presented here ADL would not be sufficient. No camera JPEG controls would make it possible to take the photo I took. And to take the photo I took my exposure setting did not consider the subject.

So how did I set exposure with a digital camera? CAVEAT: got to save and process the raw files and it's really simple. Look at the JPEG my camera created for that scene. That is a perfect exposure for that scene because I set the exposure to capture as much data as the camera sensor was physically capable of recording. I set that same exposure for every photo I take unless circumstances force me to expose less in which case I expose as much as possible. Methodology: I place the brightest diffuse highlight (clouds in this scene) at the sensor's saturation threshold and -- click. To determine that I use the camera's highlight alert system (some tuning required). I do that without consideration for the subject. No Zone System, no fuss or confusion, just the same exposure for all photos = expose the sensor to it's recording capacity. With a modern digital camera that's going to cover the overwhelming majority of what I want to photograph. The rare case where the subject/lighting contrast exceeds what a modern camera can handle, I walk away.

 

[Grandpa Ron]

Here is the issue. I am shooting B&W in a 1909 4x5 camera. No bells no whistles.

Watching YouTube, the photographers say they measure the Shadows and the Highlights. Then they use a rule of thumb that says. "Expose for the Shadows and develop for the Highlights. This sounds good, but suppose your subject is an old dark weathered bronze statue or a newly dedicated white marble statue?

On a sunny day, the Shadow to Highlight range may be several stops, but on an overcast day, perhaps half that number of stops. So how do you know which exposure to use? I know that if I expose for the statues, both will come out middle gray, but this is probably not what I want.

So, cloudy or bright; the question comes down to:
* I know the f stop value of the Shadow of the scene.
* I know the f stop value of the Highlight value of the scene.
* I know the f stop value of the Statue.

How do I determine how many f stops to add or subtract to the Statue's f stop reading?

In all honesty, most of my landscape shots are such that if I shoot for the overall exposure, the newer B&W film's tonal range and the post processing manipulations, once the negative has been digitized, provide a lot of leeway. Even my few Darkroom printing attempts were okay. However, as I progress to close up and other more complex subjects; at the increasing costs of 4x5 film, B&W and/or color, messing up an exposure become important very quickly.

Film is fun.

 

[AlanKlein]

What film do you use Ron?

 

[Ysarex]

Here is the issue. I am shooting B&W in a 1909 4x5 camera. No bells no whistles.

Watching YouTube, the photographers say they measure the Shadows and the Highlights. Then they use a rule of thumb that says. "Expose for the Shadows and develop for the Highlights. This sounds good, but suppose your subject is an old dark weathered bronze statue or a newly dedicated white marble statue?

If you're going to get involved in Zone System exposure control for film you really have to do all the testing up front. You can't rule of thumb it.

On a sunny day, the Shadow to Highlight range may be several stops, but on an overcast day, perhaps half that number of stops. So how do you know which exposure to use? I know that if I expose for the statues, both will come out middle gray, but this is probably not what I want.

So, cloudy or bright; the question comes down to:
* I know the f stop value of the Shadow of the scene.
* I know the f stop value of the Highlight value of the scene.
* I know the f stop value of the Statue.

How do I determine how many f stops to add or subtract to the Statue's f stop reading?

Do all the testing and you need to have a spot meter. You have to determine from meticulous tests what N development is and what N+1 development is and what N-1 development is etc.

In lieu of all that you could try a more simple approach. As you note below you could just use the overall exposure for the scene and then note if the lighting is high contrast (sun) or low contrast (overcast) and then just pull the development time say 10-15% for sunny and extend the development time say 10-15% for overcast images.

In all honesty, most of my landscape shots are such that if I shoot for the overall exposure, the newer B&W film's tonal range and the post processing manipulations, once the negative has been digitized, provide a lot of leeway.

This adds a complication given that you're scanning and not printing the negs. You have more control with a digitized neg.

Even my few Darkroom printing attempts were okay. However, as I progress to close up and other more complex subjects; at the increasing costs of 4x5 film, B&W and/or color, messing up an exposure become important very quickly.

Film is fun.

 

[bulldurham]

Buy all three of Ansel Adams books on this subject: The Camera, The Negative and The Print. Then, and only then will you know how the Zone System really works and how you can use it to make the same kind of stunning photographs he did. You can get all three on Amazon's Kindle for about 13 bucks apiece.

 

[smoke665]

On a sunny day, the Shadow to Highlight range may be several stops, but on an overcast day, perhaps half that number of stops. So how do you know which exposure to use? I know that if I expose for the statues, both will come out middle gray, but this is probably not what I want.

So, cloudy or bright; the question comes down to:
* I know the f stop value of the Shadow of the scene.
* I know the f stop value of the Highlight value of the scene.
* I know the f stop value of the Statue.

How do I determine how many f stops to add or subtract to the Statue's f stop reading?

I think you might be overcomplicating things. The Zone system consists of a gray scale of 11 tones from pure black to pure white. It doesn't consider color, and is exactly how a camera meter reads exposure. Meters are calibrated to read a fully exposed image at 18% reflective, or zone V. Each of the five zones on either side are exactly one stop plus/minus. Determining the dynamic range can get complicated in that in an uncontrolled lighting environment it could easily exceed 11 stops, and requires a certain amount of experience in reading the light, sometimes you can't capture the full dynamic range of the scene.

In your example If you take a reflective reading of a white statue you've established the correct exposure for that spot at zone V. Experience in reading the light comes in, (is it pure white or beige, or dirty white). It's up to you to read the subject, and determine the zone and corresponding adjustment. As mentioned above testing, practice, and meticulous notes will help tremendously.

Worth noting, any adjustment to exposure or development times are general adjustments that affect all the scene, equally. There's only two ways to change the individual exposure value of parts of the image. You can add/subtract light, or dodge and burn.

 

[webestang64]

You better make sure that your film development is spot on the same every time. Same film with the same developer and the same times/temp/agitation etc..... Consistency is key to the Zone system.

 

[Grandpa Ron]

Thanks for the explanations and suggestions. It becomes clear that the Monochrome programming on my DSLR contains a large amount of technological wisdom so to speak. I am not going to abandon digital any time soon, it is too fast and too easy to get great photos, in color or B&W.

Still, having grown up with a 1950's vintage Brownie Holiday point and shoot camera, I remember buying my first Twin Lens Reflex and the thrill of being in control of the shutter and aperture. So too when I resurrected my uncles old 4x5 view camera.

It has been a steep learning curve and after reading Ansel Adame's book triligy, I realized that, as mentioned, a lot of film photography require intuition as where to set the subject exposer in relation to the overall scene.

I have been working with the less expensive Arista EDU and FPP films, because of the cost. I have posted some of my better photos, but there is still a hesitation when I set the exposure.

 

[smoke665]

have posted some of my better photos, but there is still a hesitation when I set the exposure.

I'm not sure it's an exposure problem it's been 40 years since I did any processing but these look like either a light leak at some point or something amiss in your processing, that's causing significant lack of contrast.

The following is a scan of a print I did about 45 years ago. About all I remember is it was Tri-x (because that's pretty much all I used then for the newspaper), developed and printed on Kodak paper in my darkroom. It hung on my office wall for 25+ years or so, before I finally took it down and put it up. Initially it was crisp but you can see the fading that occurred especially in the blacks after years of light exposure.

 

[snowbear]

The Zone system consists of a gray scale of 11 tones from pure black to pure white. It doesn't consider color

About the same as a typical exercise in beginning art (drawing) classes: 10 "values" from white to black, usually done with charcoal.

 

[Spirit Vision Photography]

Picker simplifies it a bit.

Amazon product ASIN 0817405747

 

[Grandpa Ron]

I guess I oversimplified the situation.

I said I like to meter on the object I am shooting but that is an oversimplification. The pictures I posted were examples of metering the entire view, they are typical of the photos I take.

However, when I want to shoot snow, I do not want the snow to be middle grey, so I have to open the aperture, based on the snow's spot meter reading. This was also an issue out West where the bright desert sun had turned everything to a narrow range of "shades of brown".

Looking at a landscape scene and deciding on what or where to place the middle grey is not so simple, I use my best estimate (guess) and the latitude modern films. Using a spot meter can provide the Zone System exposure range, but it cannot tell you where to place the middle grey.

I have been told that looking through a color filter can help by simulating a monotone view.

 

[Spirit Vision Photography]

I guess I oversimplified the situation.

I said I like to meter on the object I am shooting but that is an oversimplification. The pictures I posted were examples of metering the entire view, they are typical of the photos I take.

However, when I want to shoot snow, I do not want the snow to be middle grey, so I have to open the aperture, based on the snow's spot meter reading. This was also an issue out West where the bright desert sun had turned everything to a narrow range of "shades of brown".

Looking at a landscape scene and deciding on what or where to place the middle grey is not so simple, I use my best estimate (guess) and the latitude modern films. Using a spot meter can provide the Zone System exposure range, but it cannot tell you where to place the middle grey.

I have been told that looking through a color filter can help by simulating a monotone view.

That's the beauty of the Zone system. YOU decide where to place the grey values in your image. Decide what is the darkest shadow in your image that you want detail in, expose your neg to drop it into Zone 2-3, and develop your negs (film), to place the highlights where you want them, Zone 8-9, etc.