THE VIEW FROM HERE
When starting the Death of the Zone System series I really didn't expect the topic to become so sprawling. With great naiveté I assumed each post would cut through misconceptions like so many weeds until the Zone System was clearly revealed. Then, each post not only left me bemoaning my lack of preparation and failure to provide a clear overview of the subject, but also left me holding fragments of questions. Writing each post has been a difficult ascent to a height where I can observe the vast landscape of the topic. However, at this point I feel the need to pause, look back at the route taken, and peer out into the distance in order to obtain some perspective.
While the instructions and claims about Zone System online are arrayed on a spectrum from comprehensive to confused common mistakes are found throughout. I can distill these errors into two categories of being overly simplistic and/or incomplete. The simplicity becomes immediately apparent by noting whether the article or blog begins with the same subject as the first chapter of Adam's The Negative, with a discussion of visualization. The loss of this central concept pulls the rug out from under the photographer because the entire system is held together by the artist's ability to see the final image in their mind's eye. Lacking visualization when making an image is akin to the construction of a piece of furniture without having a design in mind. By shortcutting this central concept and jumping straight to Zone definitions and exposure is the same as telling someone the first step in building a chair is to go buy wood. If visualization is not addressed at the beginning (or for that matter entirely) then one must be suspicious because what follows is mere technical regurgitation.
Secondly, since ZS ties together the entire process from subject to final image the explanation must include control of each step in the photographic chain. In fact, most articles stop after exposing the film or electronic sensor. Fewer go further to address how to work with the image in a computer to obtain the desired tonal values. I have found only one book and one website that actually guides the photographer all the way through to the print or an end product. Here is a quick survey but the bottom line is that the bulk of information available on-line reduces Zone System to a mere exposure tool.
DPAnswers.com - Good technical info but lacks discussion of visualization and ends with the image in the computer.
Outdoor Photographer, Ken Rockwell, Photography.Tutsplus, - Merely discussions of zone definitions and their relation to exposure.
Alan Ross - Since Ross worked with Adams I'm not surprised that he included visualization, but I'm surprised his also ends with exposure.
Martin Bailey - Fails to discuss visualization but at least gives a really solid technical rundown on calibrating a digital system for Zone System. Also, doesn't really go beyond the image on the computer screen.
Beyond the Digital Zone System - Not surprising that by far the best explanation and application to digital is by someone who read Beyond the Zone System. Does cover the entire imaging chain and begins with whole section on visualization.
Is there any reason for these publications falling short in their explanation other than maybe lack of research or understanding? In fairness, I must admit that ZS is easier applied to analog, not because it was created in the analog era, but rather that the process has a very clear workflow with rigidly defined procedures. In an effort to illustrate this I created the following flow chart.
N.B. - This analog workflow chart is a first draft. I'm not entirely happy with it and will be showing it to colleagues for feedback. Nonetheless, I think it does show the simplicity of the system and also what I believe to be its biggest failing which is the drop in MTF from step to step.
Compare this to the digital workflow chart which, while certainly possessing more flexibility with the use of computers to adjust images, is obviously more complex.
Digital workflow is so convoluted and sprawling I really struggled to create this sketch. Any feedback is welcome. What I do find important to observe is how each output from the camera requires very different technical settings.
We should be careful about falling into the "digital is simpler" trap just because one can change the color or contrast with the click of a mouse. In fact, there are many mis-matches in this diagram between the gamma and color gamut of your monitor and the output, plus transitioning to a different format results in a loss of quality. For example, it is easy for me to post my photos on-line but why does Squarespace crush my midtones? Why does their resizing algorithm for the web also affect my tonality? I could try to carefully calibrate a LUT for my photos that will be posted on Squarespace but as some point I have to give up based on the fact that most people viewing this will not have the same calibration as my monitor. All the technical differences between each link in digital workflow is also embarrassingly present in the motion picture industry where many filmmakers are using a gamma of 2.4 on the monitors on set with which they judge exposure, then color correct the image on a computer monitor set at 2.2 gamma, to finally project the image at a gamma of 2.6 in theatrical projection. Try to wrap your head around handling this explosion of possibilities when figuring out the sensitometry for digital! I am not claiming that the various standards amongst these outputs will never be reconciled, but at this particular time this is truly a mess.
Along with the tangled web of digital standards is a lack of sensitometry information for digital processes. The principles of this science are well documented for analog and one can find books as well as a free explanation on Kodak's website in their Basic Photographic Sensitometry Workbook. The practices are so powerful that one can take any manufacturer's supplied graph and easily determine critical information about the Subject Luminance Range for a film/print combination, the exposure index, and the relationship between Zones to help with light metering a scene. Perhaps a favorite example of mine is how I used Fuji's own graphs to determine that Eterna 500T really had an ISO one stop slower than the EI they published. The evidence is shown below:
From Fuji Technical Publication KB-501E. I have put in marks for the minimum and maximum useful densities for printing to Kodak Vision Color Print 2383. Take a look at where these coordinates intersect the x-axis, which Fuji usefully marked out in camera stops. According to this diagram the film has more overexposure room than underexposure. Actually, any sensitometry expert would realize that Fuji is claiming a higher EI for their film then its actual ISO. (Yes, they can do this because only ISO testing and quantification is regulated whereas EI is just a published recommendation.)
The over and underexposure range is perfectly balanced if one overexposes the film by 2/3 to 1 stop. Originally I found this out through extensive testing of this film in one of my classes in 2010 when we all agreed that visually the film looked best overexposed a stop and printed to look normal. Only a year later I looked at this chart and realized our special discovery was actually just correctly rating the film at 250 ISO.
I can find many tests for digital cameras regarding their dynamic range or either chart or graph form but these are largely for marketing and rarely contain actual sensitometric or photometric data to help the user on set. For example, look at the chart Arri created in 2010 with the release of the Alexa demonstrating how changing EI shifts the dynamic range and provides important data for light metering in these situations. For three years Red published nothing comparable but only the mere dynamic range quantity. Arri should be applauded for being rather frank in revealing this data.
(Left) Arri's chart to demonstrate how exposure latitude changes with EI adjustments. (Right) Red's first diagram of something similar three years later. Notice how much more intuitive to read and informative the Arri chart is in comparison to the Red chart which lacks any helpful information for use in the field.
The reluctance or flat-out lack of information provided by digital camera manufacturers really ends up hurting the consumers in terms of their technical intelligence about the medium. This in turn hurts photographers better understanding how to apply a practical methodology for exposure and tone control, such as Zone System provides, to their chosen materials. However, I guess creating this confusion does keep their customers ignorant in a way that helps them sell cameras.
So, regardless of my despair at the state, or perceived state, of Zone System education why should I make it such an issue? Mostly because students find it useful and I don't wish for it to die a death of neglect and misinformation. But when an inundation of mediocre explanations washes away better resources then it saturates the information landscape and sows the seeds of confusion and ultimately disappointment for the amateur photographer trying to put it into practice. Do I have any proof of these lost ZS practitioners? Sadly, nothing statistical, but I do have the characterizations of ZS that students bring to me when they begin my class, as well as their questions regarding aspects they find confusing. I can report that despite their initial lack of understanding they have a strong intuitive sense that it is worth learning and will be a useful tool on set.
I hope these writings help heal the wounds from such ignorant and disparaging comments such as this:
An example from photo.net of advice from someone who has already made up their mind and is unwilling to change it. His characterization of ZS and sensitometry makes me suspicious that he understands either. To claim sensitometry is important but ZS is not is like saying that all we need is Bernoulli's Principle, but not the joystick to fly the plane. The analogy to unsharp masking is irrelevant because this is the rhetorical trick of the strawman argument. The sign off to his post is more about his ego than an awareness that he is submitting advice to a community. I take this post as a warning that I must recognize the fact my ideas will have to change with evidence.
This form of non-advice (a negation of advice) illustrates the dwindling use and understanding of ZS is not through any fault of its own. Rather, it is a victim of its own dissemination amongst the online communities or publications that are merely producing content at expense of substance. Just go to any forum and one can read Zone System's epitaph.
Despite my rather negative tone, I actually am optimistic for the future. Since I can survey the Zone System landscape from a vantage built on years of study and practice I would be a fool to not notice even higher peaks that are within reach even though they lurk in the clouds. So, where can The Death of the Zone System series go in the future? First, I think there needs to be much more research about the human eye incorporated. Since I found there exists characteristic curves for the human in the Theory of the Photographic Process I want use this data for further understanding how tonal values appear to us at the end of the imaging chain. Unfortunately, this raises a number of questions for my industry; what is the adaptation level of the eye in a theatrical or household setting and how much does it change? Is there a point in a movie theatre where the screen fills such a large angle of view that we move from dark surround conditions to bright surround conditions? These are great questions to set out on a journey to answer.
Secondly, digital sensitometry seems non-existent. I have located information about Photon Transfer Curves but have not ascertained their relevance to ZS. I have found this article about digital ZS (and the title sounds like something I would write) but I need to go through it carefully because I find some of the claims suspect. Nonetheless, establishing digital sensitometry working methods would provide a clearer relevance of ZS to digital as well as spur the creation of better tools in image adjustment software, improved formats, and perhaps better algorithms. I get the sinking feeling that the photographic industry relies on a great number of ad hoc solutions based on earlier video standards and that decisions are based on nominal research. There is a willful ignorance of lessons that can be learned from the past and how they would be applied in the future. We need to ask more questions and perform better research. We need to get above the trees to order to appreciate the entire landscape.