It is commonly known that color doesn’t equal wavelength. Here is a popular definition of color, given by Alexei Shadrin and Andrey Frenkel:
Human color perception occurs when the light receptors are stimulated by the electromagnetic radiation of the ʻvisible’ wavelength (that is, ranging from 380 to 760 nm). The stimulus can also come from other sources, both physical (illness, injury) and cognitive (associations, hallucinations).
When observing a scene in real life, our eyes react to the light of a certain spectrum and intensity. Under these stimuli, our mind forms a perception. Logically, we can assume that by reproducing, or imitating, the real life stimuli, we will arrive at the same perception. Robert Hunt, the author of The Reproduction of Color, describes two ways of spectrally accurate color reproduction: the micro-dispersion method and the Lippmann method. Both are quite labor-intensive and require a full laboratory to be implemented. Hunt also mentions a simpler method of approximate spectral color reproduction based on using six or more differently colored dyes, inks or pigments. In our contemporary world, this method, too, is difficult to apply. Thus, modern color reproduction is based on a technique that is both simple and efficient. Hunt calls this approach “simplified”. This is what he writes:
“In view of the difficulties inherent in the micro-dispersion and Lippmann methods of colour photography, it is not surprising that they have never become popularly used, and the feasibility of using as many as six colorants is very limited. Were it not for the fact that, when the human eye views colours, it simplifies their complexity, none of the present-day methods of colour reproduction would work.
“The rest of the book, therefore, is devoted to describing the principles and methods of achieving colour reproduction by an approach that is basically much more simple: instead of all the colours of the spectrum being dealt with wavelength by wavelength, their effects are considered in three groups only, as is the case with the human eye.”
The use of these three groups of color spectrum (red, green and blue) to manage colors is widely utilized today, most notably within the international Color Management System (CMS). In the 1930s, the International Commission on Illumination (CIE, Commission Internationale de l’Éclairage) ran a series of tests, which proved that the effect of spectrally pure colors on the human visual system is identical to that of the combination of three colored beams of different wavelengths (red at 700.0 nm, green at 546.1 nm, blue at 435.8 nm).
This approximation allows for a very accurate reproduction of the visual stimuli that a viewer would get from observing a scene in real life – using any medium possible (overhead projector, computer screen, paper, etc.). But what will we see, exactly? Let us first look at the capture in Fig. 15.1. It has been converted from a raw image with Gamma set on 1.0-file as is, with no correction other than the white balance applied to it. Generally, we can assume that this capture imitates the stimuli affecting the retina as the viewer was taking in the mountain scenery. Now compare this image to Fig. 15.2 – an adjusted picture that reflects the impression that the author (i.e. me) received in real life and wanted to convey photographically. Now, one would think that by carefully reproducing the real-life color stimuli in a picture, one could also reproduce the real-life impression, but the images “tell” us otherwise”.
How so? The answer literally lies outside the image. When you are contemplating a scene in real life, your vision is only affected by the stimuli that the scene presents. When you are looking at the representation of this scene – projected onto a white wall, printed on paper or displayed on your computer screen – the periphery of your vision is also receiving the stimuli of the background, which can include lighting conditions, paper color, color of other objects in your line of vision, etc. Our visual system adapts to the conditions we are in, so that our eyes adequately perceive the whole scene – not just a small representation of another scene within it.
Figure 15.1.
Figure 15.2.
If we could exclude the visual noise, our visual system would only adapt to the stimuli produced by the mediated image and lead to a life-like impression. Unfortunately, we cannot exclude the background completely, but even a partial exclusion of visual context will illustrate my point. For this, I will place the image against a black background (see fig.15.3).
Figure 15.3.
Then, I will ask you to roll a piece of paper and look at the image though this makeshift tube for twenty or thirty seconds. Note how the picture gradually becomes more vivid, and how the snowy peaks of the mountains assume a pale shade of pink. Now, remove the tube and quickly return to the original image (the one in the white background). I have staged this experiment countless times, in a dark room with the image projected on the wall, and I can account for the reaction of at least a thousand people. All of the participants, without exception, noted the change in how they perceived the white-background image: coming back to the original picture was a disappointing experience, as the image would look bleaker and less nuanced than before. There are several important conclusions to be drawn here:
1. Any objectivity in color reproduction lasts as long as no human perception is involved, i.e. up to the moment when the spectrally accurate representation or imitation of a real-life scene finds its viewer. Regarding the viewer, we can only talk about subjective perception, which is pivotal to creating the final impression. Although people perceive colors in a mostly identical way (as had been demonstrated by the CIE tests), their impressions are vastly different. To illustrate, I will compare two interpretations of the same scene by two different photographers. One of the pictures is mine – the one we used at the beginning of the chapter – and the other has been taken by my good friend and fellow traveler Vladimir Trofimov.
Figure 15.4.
Both images were captured in Barskon, Kyrgyzstan, from the same vantage point –and at the same time (fig. 15.5). Our cameras – identical Canons (5D Mark II) – were pointing in the same direction and we were shooting with identical settings (the ISO, exposure and shutter speed were almost the same). Yet the resulting images are vastly different. Not in the sense that one is necessarily better than the other (I happen to like both of them), but meaning that we managed to convey different impressions from a scene that would – at least theoretically – have the same objective visual impact on both of us. For my friend, it was important to reproduce the entire magnitude of the mountain view, whereas I was clearly more fascinated by the blood-red coloring of the snowy peaks basking in the sunset.
In photography, “honesty” ends when you make your first choice. Usually, it’s the choice of the lens you are going to use, way before you reproduce a scene or post-process an image. So the question whether the captured image represents the way things looked in real life is, in fact, the question of who and how was doing the first “looking”.
2. Human color perception depends on the viewing conditions and periphery. There is no “honest” photography, but there are specific “honesty-demanding” tasks, like catalog product photography, and there are tools for solving these tasks. What are these tools? Predictably – standardization of viewing conditions, as described, for example, by ISO 3664:2000, Viewing Conditions. Graphic Technology and Photography. This just means that there are ways to more or less accurately reproduce a real-life scene, yet these will only work as long as we follow the viewing conditions. Any perceived accuracy is lost the moment the viewing conditions are altered, and even the slightest change will have its impact.
Moreover, product photography is not only about the honest representation of goods for sale; it is, in the end, about boosting the said sales by impressing a potential customer. Of course, it is important to get the colors (mostly) right, otherwise the customers will complain. But it is equally important to present the product in the most favorable light, angle and context. These are the parameters that are set at the moment of shooting. Post-processing takes care of saturation and contrast (these are generally increased), small defects (these are generally removed) and a number of other details.
Quite literally, we are not paying for what we are getting, we are paying for what we want to get. When our catalog items arrive, we tend to ignore their minor flaws, especially when we remember the image that “sold” us the item. It is often the case that we like a thing – or even a person – because their photographic image has first impressed us, whereas in real life they are not quite as stunning.
3. No image is shown unprocessed. Ideally, post-processing accounts for very specific viewing conditions. In practice, however, the viewing conditions that serve as a reference are fairly generic. I cannot stress this enough: post-processing is vital and it always happens. If it didn’t happen, all images would look as bleak and unimpressive as the one I have shown in fig. 15.1. Those who insist that they print their JPEG-files directly from the camera or raw converter do not understand that some post-processing will still have happened. In this case, the decisions are “made” by the camera or the pre-set values in the raw conversion software, and the user just okays the result.
If you open a raw file in any raw converter, you will see an image that has already been processed one way or another. For example, in Adobe Lightroom 4.0 or Adobe Camera Raw 7, the processing is set as default, although many of the values are pre-set at 0 and the tone curve is a straight line. In the earlier versions of the software I have just mentioned, a user could opt out of some of the defaults. One of them was an S-shaped tone curve that would translate into darker shadow values. The very existence of this particular default tells us that someone in the Adobe team has a working understanding of color perception in art. The aim of Adobe defaults is to make sure the image you get looks similar to the one you have seen on your camera preview screen. In Figure 15.5 you can see how the defaults are set for Adobe Camera Raw 6.10
10 Applying post-processing defaults in Adobe Camera Raw 7 will yield similar results, although the user interface is slightly different from the previous version.
Figure 15.5.
No matter how happy or unhappy an average user may be with the result of applying the presets, they will hardly say that the image has not undergone any post-processing at all. If you are shooting with film, you make the same leap of post-processing faith – this time, you place your trust in the hands of the team of engineers who have designed the chemical make-up of emulsions. In this case, the resulting image is likely to be more vivid and even more pleasing than the one you may get through applying your digital camera defaults. When it comes to film photography, colors, in particular, tend to be less “faithful” – but generally more appealing, too. We already know that this appeal is not accidental: previously, I have already mentioned that companies producing photographic films invest a lot in the research of color aesthetics.
Whether we want it or not, we will have to adjust an “honest” image into one that is more suitable for our perception. In other words, we will have to process the initial flat snapshot of reality so that it better fits our fairly generalized understanding of the viewing conditions, otherwise the beauty of the scene may be lost on the eventual viewer. Having understood that, we also have to admit that photography is not a mere reflection of reality, but rather an artistic interpretation of it.
Take the image that we have started the chapter with, for example. I have proposed my take on it (fig. 15.2); now you can agree with my interpretation or propose an alternative that would better suit your taste. Your treatment of the initial image will be different – and individual, so it is very hard to talk about “honesty” or “faithfulness” to the original scene. You can also choose to apply any of the standard presets to the original (fig. 15.1). Off the top of my head, here are the most typical defaults:
- Camera-generated JPEG;
- Raw converter presets;
- Shooting with film (the film itself being the result of the processing of a linear signal);
- Converter and processing software presets and defaults.
Ultimately, the choice is yours. As an author, you are free to choose the processing method, and you are free to disagree with the results of the “default” processing, just as those who shoot with film choose the make of film depending on the subject, lighting and other conditions.
Until now, we have been talking about perception. Next, we could delve deeper into the processing matters, which are quite fascinating, to be honest. Because this is where the authorial intent is to be found. This is where we can discuss aesthetics and the art-photography agenda (which, incidentally, never bothered with “reproduction of reality”). However, since this book has a different aim, I will have to cut myself short here and humbly give the floor to the practitioners:
“One of the biggest mistakes a photographer can make is to look at the real world and cling to the vain hope that next time his film will somehow bear a closer resemblance to it… If we limit our vision to the real world, we will forever be fighting on the minus side of things, working only to make our photographs equal to what we see out there, but no better.”
Galen Rowell
“There is no such thing as inaccuracy in a photograph. All photographs are accurate. None of them is the truth.”
Richard Avedon
“Photography, as we all know, is not real at all. It is an illusion of reality with which we create our own private world.”
Arnold Newman
“You don’t take a photograph, you make it.”
Ansel Adams
Andrey Ariev, in The Teller’s Tale, his introduction to one of Sergey Dovlatov’s books, writes along the same lines (albeit about literature, not photography):
“The reality of fiction is more important for a writer than the reality of fact. He would avoid reconstructing events by letter only to allow for a literary interpretation of them in his prose.
Figure 15.6. Viktor Borisov-Musatov, Cabbages, 1893
Finally, a quote from a Russian artist, Vasily Polenov, where he reviews a painting (fig. 15.6) done by his colleague, Viktor Borisov-Musatov:
“Here is a prime example of wild-life. Where’s the life, you will ask. Here: in the artistic impression, rather than in the thoughtless reflection of the scene. Look: there is no sky to be seen, but its color is visible on the leaves of the grass, on the trunks of the trees. It is there, and it sets the mood. And look at the ground – it is not dark brown, as you would expect the ground to be, but pale lilac, as it should appear in this light. The impression is not objective; it is a pure plein-air, artistic truth.
LIFELIKE: A book on color in digital photography
Dehancer Blog 