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From the beginning of my project my aim has been to capture some of what remains of the architecture of the industrial era in an attempt to represent this period of time through modern digital technology and in this way make a connection between our current digital revolution and the industrial revolution of the 19th & 20th century.
This essay is a reflection on my two year journey into the project, on my learning, development and contextualization of ‘Industrialism brought forward’.
This is the link to the PDF file of my essay
The Zone System long associated with Ansel Adams and Fred Archer is a technique used to learn how to pre-visualize. Pre-visualization stands for the act of looking at a scene with the physical eye and seeing in the mind’s eye how a medium such as traditional black and white photography can render the subject.
The Zone System is a good methodology as it demystifies technique. Understanding it allows a simplification of the traditional photographic process (exposure, developing and printing). By getting perfect negatives with a precise exposure you reduce the time of post-production to get the results you desire.
TECHNIQUE
The Zone System splits any given scene into tonal zones, 11 steps of tonal values which the human eye can recognise. Adams and Archer took the spectrum of print values, from black to white, and, using f-stops as the standard of measurement, simply assigned a Zone to each value that each f-stop of exposure produced. This results in a Zone Scale, which is a visual representation of PRINT values from black to white. This technique can also be applied to colour negatives.
Zones are always represented in Roman Numerals. Zone 0 represents the maximum black that the print can produce. Zone X represents pure paper-base white – no image. The mid-grey is in Zone V, the middle of the scale.
The light meter provides exposure settings for Zone V, giving a correct exposure for a known Zone. That’s the starting point. By adjusting exposure the subject can be placed in any Zone, up or down the scale, from the starting point. The subject will assume the tonal value of the Zone in which it is placed.
“Expose for the shadows; develop for the highlights.”
Zone placement can be also controlled by the development of the B&W negative.
Shadow density is controlled predominately by exposure. Highlight density is controlled predominately by developing time. A little additional development will not significantly affect shadows, but will push highlights up the scale. As developing time is increased, negative densities increase, but highlight densities will increase the fastest. Therefore, contrast also increases with increased developing time. This is referred to as N+1, “normal development plus additional development to achieve one additional Zone.” N+2 implies two additional Zones.
Zone description
| 0 | Pure black |
| I | Near black, with slight tonality but no texture |
| II | Textured black; the darkest part of the image in which slight detail recorded |
| III | Average dark materials and low values showing adequate texture |
| IV | Average dark foliage, dark stone, or landscape shadows |
| V | Middle grey: clear north sky; dark skin, average weathered wood |
| VI | Average light skin;light stone; shadows on snow in sunlit landscapes |
| VII | Very light skin; shadows in snow with acute side lighting |
| VIII | Lightest tone with texture: textured snow |
| IX | Slight tone without texture; glaring snow |
| X | Pure white: light sources and specula reflections |
Digital photography
The Zone System can be used in digital photography just as in film photography; Adams (1981, xiii) himself anticipated the digital image. As with colour reversal film, normal procedure is to expose for the highlights and process for the shadows.
One way to expose a photograph correctly with a digital camera using the camera’s little LCD window, would be to take a quick reference meter reading of your subject and note where the histogram falls on the scale from right to left.
A histogram shows the concentration of tones, running from dark on the left to light on the right, it can be used to judge whether a full tonal range has been captured, or whether the exposure should be adjusted. Varying the exposure one or two stops would correct the image if it is too dark, the histogram should be as far right as it needs to be to avoid the problems caused by expanding the contrast.
Digital camera previews are generated based upon different assumptions, one of those assumptions being that the image is being taken as a JPEG. This means that when shooting RAW files the histogram that the camera creates won’t precisely match the one that will eventually be worked on. Raw files can recover highlights that may seem to be “blown out” on the histogram.
Applying the Zone System maybe a better way to take a correct exposure. The subject highlight values can be placed accurately on the Zone Scale. It is a similar system to that used with colour reversal film. In this case the subject needs to be exposed for the highlights.
If your in-camera light meter has a spot metering function, or if you have a hand held spot meter:
- Carefully meter the Zone VII important highlights of your subject
- Make note of the meter’s recommended exposure
- Since Zone V is two stops darker than Zone VII, opening up two stops from the meter’s recommended exposure for the textures highlight will accurately place them on Zone VII. This will be the perfect exposure for digital cameras. EG: 1/125 @f/22 becomes 1/30 @ f/22
HDR
Another method of getting great scene contrast can be accommodated by making one or more exposures of the same scene using different exposure settings and then combining those images.
Automatic layer alignment in the image editing software makes this combining easier. The image then can be combined in HDR software that assists precise registration of multiple images.
Similarly to traditional photography we need to take into account the postproduction on a digital image, every step is important. The tonal range of the final image depends on the characteristics of the display medium. Monitor contrast can vary significantly, depending on the type (CRT, LCD, etc.), model, and calibration. A computer printer’s tonal output depends on the number of inks used and the paper on which it is printed.
Digital exposing for the highlights
It should now be clear that there are important technical advantages to properly exposing digital image files, but using the Zone system with 35mm cameras always requires some extra efforts.
With roll film cameras the problem always is: how to apply individual contrast control to frames that must be developed together. That isn’t a problem with digital 35mm frames, but there is still the issue of metering selected areas with built-in light meters.
Since it’s so easy to preview digital photographs using the camera’s little LCD window, one practical solution would be to take a quick reference meter reading of your subject and note where the histogram falls on the scale from right to left.
If the image is too dark, you could simply open one or two stops using either apertures of shutter speeds until the histogram is as far right as it needs to be to avoid the problems caused by expanding the contrast.
Moving the histogram too far to the right would be overexposure and cause the subject’s highlight values to fall off the edge of the histogram where they would be lost.
This is a very quick and very simple exposure method (and this is what many digital photographers actually do), but there is one issue that, shooting raw image files makes this approach less precise that it appears to be.
As mentioned above, digital camera previews are generated based upon assumptions about how you will eventually want to use the image. One of those assumptions is that you’re shooting for jpeg images that are compressed. When shooting in raw format, this means that the histogram the camera creates won’t precisely match the one you will eventually be working with. This issue also applies to the flashing ‘out of gamma’ highlight warnings that are a function of many digital slr cameras. When the preview is set to this function it can give the alarming impression that the highlights are blown out when, if shooting in raw format, they may be recoverable.
The aim when I took these pictures was to learn about how to photograph interiors and get the maximum tonality out of the negatives. I am learning about the Zone System which is very useful to know if you want to achieve detail in highlights and shadows and also I am developing the film pushing the amount of time (or giving N+1 development) so that the upper zones or highlights have been pushed up a further zone but the shadows and lower zones stay where they are achieving this way a greater tonality.
I have a diagram that explains what happens to the tones with different developing times (the roman numerals refer to the different tonal zones):
To get an even better tonality I developed the film for 20 minutes and the developer was diluted in a 1-100 proportion. I used Rodinal which was patented by Dr. Momme Andresen in 1891. It is the oldest continuously-produced developer formula in the world. At high dilutions Rodinal works as a compensating developer, which means that as the chemicals get exhausted they stop working on the highlights but continue working on the mid tones, thus preventing blown highlights.
There is an useful website to get correct times for developing, it is www.digitalthruth.com
The film I used is Rollei Pan25 which, according to the ad, offers outstanding resolution, sharpness and edge contrast, coupled with extremely fine grain and a long tonal range. This film is ideal where maximum quality is required, and its clear base makes it perfect for scanning. The only fault is that the film is quite thin and it curls a lot making it difficult to scan the negatives an quite fiddly in general.
I took this pictures with a classic medium format camera ( Hasselblad Super Wide). This is the technical data for the following images:
Colour Darkroom:
Meter readings: the floor was on zone II and the sink on zone VI
Aperture: f11, 6 minutes
Sculpture workshop:
Meter readings: the girder was on zone II and the sink on zone VI
Aperture: f11, 150 seconds
Type room:
Meter readings: the back of the room was on zone II and the highlight under the fluorescent light on zone VII
Aperture: f11
