From time to time on the Internet, including several times in the comments to Ctein's post yesterday, I hear people wish that digital SLRs had an automatic "expose to the right" mode that would put the histogram right up to the right edge, meaning no highlight pixel would be saturated and the maximum value would be achieved for all the rest. Theoretically, for any given scene—even those that exceeded the dynamic range of your sensor—this would give you the most to work with in software, maximizing shadow detail and contrast and minimizing noise.
Sounds good, right? For many scenes it would be. Maybe it would even be useful, overall.
The reason it wouldn't work all the time is that there are plenty of occasions when you want your highlights to overexpose. In the kind of shooting I do, I encounter them often: A dusk scene sprinkled with pinpoint streetlights and house lights; a lonely winding road with a single car's headlights coming at you in the middle distance; backlit bright afternoon summer sunlight sparking on windswept water.
These are examples of the many scenes that have in them what are called "specular highlights," a generalized way of referring to accent highlights that are off the scale—the kind that in traditional black-and-white photography would be purposefully rendered as "paper white." If a camera's meter could detect these and put them within the scale of recordable values (tones)—"expose them to the right"—then the rest of the exposure might be so far wrong as to not be salvageable. The most common example is probably just the sun in the picture, assuming your lens is good enough not to flare out.
(Ansel Adams once performed an unusual virtuoso trick with the sun. Utilizing partial solarization, a peculiar property of film whereby extreme excess exposure not only triggers a failure of the reciprocity law but also results in less negative density, he created a picture (in Portfolio V, 1970) called "The Black Sun, Tungsten Hills, California," in which the disk of the sun is rendered near-black and the rest of the picture is exposed normally and not solarized. I suppose that's not really pertinent here, but it's a nice anecdote. Incidentally, Portfolio V was the first of Adams's portfolios he printed large, on 16x20 paper, and for which he used older negatives, and he committed to never printing any of those negatives again. Despite this limitation, few of them are now among the most valuable Adamses.)
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A picture of Adams you've never seen before: Ansel Adams, Photo Booth Self-Portrait, c. 1930, from the collection of the Archives of American Art, in the Katherine Kuh papers. If he could have obtained the negative from the machine, he probably would have tried to print it better!
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Last night I snapped the "record shot" shown above of our house all dolled up for Halloween (handheld at 1/5th of a second and dead sharp, O ye who doubt the usefulness of IS—but I digress. Again). In this shot, would you really want the camera to "place" the luminances of the electric pumpkin next to the steps "to the right," so that none of its pixels were saturated? If it had, I would have lost an unacceptable amount of shadow information off the left side of the histogram—much more than I actually already did lose. The picture would have been useless. There are many such situations in real-life shooting that would require operator intervention if such a feature existed. There's a reason why "averaging" metering is so effective.
Incidentally—I digress yet again—we had a nice Halloween, with about 250 trick-or-treaters. Generally, we have an exceptionally attractive cohort of rug rats in these precincts, and the little chuppers are very polite. For a while I had to stand out front, because a fair percentage of four- and five-year-olds find our house sufficiently scary that they won't come up to the door. The strangest things I saw were a) a teenager elaborately dressed as a toilet, and b) three middle-aged Hispanic women dressed in black plastic bags over their clothing actually asking for candy. I don't know—recent immigrants who aren't quite clued in to the subtleties of the holiday yet? Beats me. Apart from such anomalies it was a very social evening, a chance to see neighbors seldom seen, with family bands roaming up and down the streets and lots of animated conversation.
But back to our topic. Cameras do an awful lot for us these days—including, now, providing a near-instant "Polaroid" so you can check your composition and focus, and (on some cameras) tricolor histograms so you can check exposure in every color channel. Sci-fi stuff by the standards of, say, Ansel's lifetime. But no matter how much our cameras do for us, there's never—I mean never—going to be a mechanical-electronic means of getting every exposure just the way you want it, if only because "perfect exposure" is forever going to be partially a matter of taste and individual intention, at least occasionally. For better or for worse, the best way of creating the best exposure includes the application of of experience and judgment as well as the use of the measurement device between your ears along with all your other measurement devices...however sophisticated the latter might be.
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Mike
Featured Comment by Thom Hogan: Obviously, 'it wouldn't work all the time.' Current metering systems don't 'work all the time' either.
But would Mike object to an Ansel Adams Zone System spot meter that gave you a precise indication of where other values were if you were to assign one reading as Zone X or I? Somehow, I think not.
Because this is a highly visible site, I worry about seemingly outright rejection of an idea, as it often causes the camera makers to reject more than the basic idea. Let me see if I can explain.
One problem with digital is that it is indeed linear and so much of the lower half of tonal range is recorded in so few bits. Besides meaning less capable tone ramps, it also means a lower signal-to-noise ratio for the low exposure zones.
The other problem is this: we don't know what our cameras are telling us. That's particularly true if you shoot raw, as the histogram and highlights display isn't based upon the actual data, but an interpretation of the data (the embedded JPEG, demosaiced with the camera settings). Worse still, not a single manufacturer that I know of has revealed at what point their highlights display triggers. Essentially, the camera makers are assuming we're not very smart and they're trying to protect us from ourselves.
We really need several bits of information:
1. How much of the scene has photosite saturation (well overflow) in it.
2. Where that saturation lives in the scene.
3. What channel(s) that saturation lives in.
4. How much of the scene has photosite underutilization*.
5. Where that underutilization lives in the scene.
6. What channel(s) that underutilization lives in.
7. What the underutilization assumption is (and this is one that should be user changeable; some people have more aversion to noise than others).
8. Histograms on well data in the range between saturation and underutilization.
*We don't have a good name for this. I use underutilization as meaning the point at which the SN ratio drops below a certain point, essentially defining the point where pulling out additional detail is impossible to distinguish.
If Mike had all that information, he'd actually be more capable of interpreting whether the blowout his camera is telling him he has is really what he wants and whether the rest of the exposure is working. But we're not likely to get that information if camera makers think that anything relating to expose-to-the-right (ETTR) is going to be rejected by a significant portion of the shooting public.
In the picture he shows as an example, we've got a lot of the frame rendered essentially with no detail. He very well may want it to be that way (after all, Halloween is supposed to be spooky, and low/no detail is supportive of spooky), but let's say there was a face in one of the windows. Does he have it in his exposure in a way that he can work with it in post processing? You wouldn't know with the current camera exposure helpers. And, yes, an Auto ETTR would worsen that problem. More on that in a moment.
The point is that most of us who talk about anything related to ETTR really are asking for more, and more accurate, information about the exposure. Since in digital we can review the exposure immediately, it makes large sense to make sure that the information we have is optimal in that respect. It currently isn't.
The idea of an automatic expose to the right exposure mode is akin to Program exposure mode or (ahem) Scene exposure modes. It would thus obviously be targeted at novices who don't know what they're doing or don't want to think about anything more than where to point the camera (and quite frankly, it would need an automatic post processing companion to bring the exposure back to visually appealing).
Mike is right in that every time we cede control to an automatic control, we give up some of the decision-making that is integral to optimizing the making of a photograph. Sometimes we do that because we're not sure we can make those decisions fast enough (autofocus comes to mind), but most pros think seriously about as many of those decisions as they can for every picture they take.
Still, right now we have to guess as the accuracy of the information we're being given to evaluate our decision-making. I'd rather not guess. Give me the right data, presented correctly. If that means that we also get an Auto ETTR mode that I'll never use but might work for someone else, that's fine with me. I can ignore those (ahem) Scene exposure modes as long as I have P/A/S/M, for example, and ETTR is something along those lines: I can ignore Auto ETTR as long as I have the info that underlies it so that I can manually control it.
So let's not try to talk the camera makers out of exploring ETTR. Let's instead convince them that there are consumer and pro aspects of ETTR and we both want an optimal set of controls for it.
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Thom
, by Jerry Dennis.
"For me, it has been always a simple matter of taste; in music, in literature, in movies and now in photography: I see/hear/read it, and if it pleases me, then it's good...if it doesn't it's not. How can art not be subjective?
"DISCLAIMER: I have no art background at all, so please feel free to 'educate' me. I would love to have an epiphany about all this; I just don't see it coming."
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Adam McAnaney replies: Thiago, I certainly understand where you're coming from. I’m a lawyer and for most of my life I had little to no interest in art. Then I met my wife, an art historian, and she has dramatically changed my view of art, particularly because of her interest in modern art. I still don’t know much about art, but I’m getting interested. Here are my thoughts:
First, I don’t think there is anything wrong with approaching art the way you have been—i.e., do I like it or not? This is indeed a very subjective approach, one based on your immediate emotional response. This is still the way I approach most art, particularly the thousands of random photographs that I view online.
But I would argue that much of art is interesting on an intellectual level that has very little to do with whether you (or I, or anyone else) like it or not. The problem is that in order to appreciate art on this level, you have to: a) study art history, whether formally or informally, e.g., through books, b) have access to a lot of an artist’s work and have the time to study it and develop an independent sense of what characterizes the artist’s work and what they were trying to achieve, or c) get the artist to explain what she or he was thinking.
Let me try to give you a few examples. The artist Masaccio painted beautiful paintings. But he is remembered today as the first artist to use linear perspective. Realizing that he helped to change painting for generations to follow helps us appreciate what he did. Michelangelo’s David is treasured today, not only because a lot of people like it, but because of the fact that Michelangelo chose to abandon the dictates of strict proportionality in forming David’s limbs. Many Cubist paintings are visually interesting, and you may like or dislike some of them on an emotional level. But I found Cubist paintings much more interesting when I found out that Cubism was a response to the problem of depicting a three-dimensional object on a two-dimensional canvas.
Now, I never would have figured out any of this stuff on my own. And if you saw a Masaccio painting without any identifying information, you would have no way of knowing whether it was painted by the innovator, the first man to paint using linear perspective, or by your next-door neighbor, who now takes linear perspective for granted, without even thinking about it. But at least you can read about Masaccio, Michelangelo and Picasso in books. Tons of literature exists to help you place these artists in context. With contemporary art, most viewers are left stranded, without a reference point to help them orient themselves. This is aggravated by two things.
First, much contemporary art is not particularly concerned with presenting something pleasing to look at. Instead, the work of art embodies a thought process or philosophy, and is intended to provoke the viewer into considering the concepts involved. The work of art itself is just a starting point for getting people to think about ideas. When Kasimir Malevich painted his Black Square, he wasn’t trying to paint a black square as such. He was making a statement and wanted viewers to consider his conceptual framework, Suprematism. You can’t understand or appreciate the Black Square unless you know something about Suprematism. But learning about Suprematism (or the ideas behind any work of art) is a dual responsibility: the viewer has to take the time to really engage with the artist, the work of art and the work’s historical/artistic context, while the artist has to be willing to engage in a real conversation and to openly discuss what he’s getting at. This is where the second problem with contemporary art lies: far too many contemporary artists are too lazy or too timid to really discuss their work. It is very easy to throw up a work of art, call it “Untitled #7” and claim, “My work speaks for itself.” It is very difficult to take the time to work out a coherent aesthetic or concept, and to then defend it against inevitable attack by critics.
On one level, we are very fortunate today. Art is probably more accessible today than it has been at any point in history. And there are more people who are engaging with art, on one level or another, today than at any time in the past. But whereas in the past art was created for and appreciated by a select elite with lots of free time, who were generally educated on art on some level and who had the opportunity to speak directly with the artists they commissioned, today’s art audience is very different. Art history is disappearing from public schools. As math and reading scores (appear to) have dropped and as the focus on standardized tests has increased, schools have attempted to raise their standing by devoting more time to basic subjects, often at the expense of the arts. Budget cuts certainly have not helped. So today art is being consumed by a far broader section of society, but one that is less educated in art history, that has less time to devote to understanding and appreciating art (given the demands of work and family) and that generally views physical works of art in museums, without ever seeing or speaking to the artist.
Many museums contribute to the problem, but not providing visitors with any information other than the artist’s name, birthplace and birth year, the name, date and dimensions of the artwork and the materials from which it is constructed. How are you ever supposed to get to Suprematism by reading “Kasimir Malevich, born in Kiev, 1878-1935, Black Square, Oil on canvas, 1915, 53.5cm by 53.5cm”? I have never understood why museums don’t provide more information to help the viewer. But this is slowly changing. One of the greatest aids to the appreciation of art in museums are those audio guides, where you punch in the number below the artwork and get a little background. No squinting at small text and jostling the crowds. I recently went to a museum in Dresden that had two copies of the same painting. One by the original artist, and a copy by artists working in his workshop. The audioguide did a wonderful job of comparing the pictures and contributing to an understanding of what was special about the artist’s work. There is obviously a risk of these audioguides or accompanying text giving the impression that only one interpretation is correct, and of limiting the viewer’s freedom to interpret the work anew. But given that most people seem to struggle with a lot of art, I think this is the lesser of two evils.
One last note: the internet is obviously a great resource when it comes to art. While viewing art on a computer screen obviously cannot compare to seeing it in person, you have at your fingertips access to representations of countless artworks and volumes of literature analyzing and describing such art (though it is up to you to judge the quality of such literature). In some ways, appreciators of photography are particularly well off. Digital photography is obviously particularly well suited to distribution over the internet. And given that so many photographers have websites with e-mail addresses and/or photoblogs with the opportunity to comment, it is possible to really follow a photographer’s development and engage in a dialogue with them. It’s really pretty amazing.
None of the above is necessary. You are obviously free to view art and simply decide whether it appeals to you or not. Like I said, that is still how I deal with most of the art I encounter. But if you take the time to learn about the conceptual side of art, I think you will find art a lot more interesting and fulfilling, and a lot less frustrating. Plus, you will be amazed by how much art and artists actually engage with the world. As contradictory as it may seem, the more you get into the conceptual, the less abstract art seems. Art doesn’t have to live in a bubble. And thinking about it will get you thinking about other aspects of life.
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Adam
P.S. This is obviously just my point of view, and it isn’t a point of view that necessarily lends itself to all kinds of art. I’m generalizing here and I welcome responses from others describing how they approach art. I would also like to thank my wife, who has really opened my eyes and shaped my views on a lot of what I wrote above.
Adam McAnaney is an avid amateur photographer. He lives with his wife Elisabeth in Germany, where he works as a securities lawyer.
Featured Comment by Huw Morgan: "I've only two things to add to this entertaining thread: First, in response to Ctein's comment where he mentions his lack of affinity for classical music. One of the wonderful things about all art is that it rewards the investment in time in a linear fashion. I can guarantee that if you spend a few months going to a music appreciation course, it will open the door to enjoyment of classical music. If you spend 30 years studying classical music, you will reap the reward 30 fold. Ditto for any art form. Second, for Thiago who started all this, there is a very lovely set of DVDs produced by the BBC that gives you a pretty complete art history course in a box. It is narrated by an exuberant nun called Sister Wendy and follows the development of art from the prehistoric cave paintings of France to the present. It can be ordered here
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Comment by Mike: Re the discussion in the comments, Adam = rice, Player = fish. See "Prejudices #2" post for key to analogy....