Photography News 08




Images or photographs?

When is a photograph not a photograph? IanMcNab attempts to answer the perennial question of how far post-processing can go before you can no longer call an image a photograph

For the last 40 or more years, art historians, critics and theorists have discussed this essential difference between photographs and synthesised pictures. They have described how photographs are physically ‘caused’ by the light bouncing off the objects they depict. And to refer to this, they say that photographs are an ‘index’ – a trace or imprint – of the objects, not just a representation of them. The ‘indexicality’ of the photograph depends on the physics of light and the optical recording system of the camera, which maps the patterns of light reflected from the 3D world in front of the camera precisely onto the 2D plane of the light-sensitive recording surface inside. This is a matter of simple but precise geometry: the distances and angles between points on the image on the surface of the sensor or film correspond to points on the objects in the 3D physical world in front of the camera. Remembering these simple facts helps with understanding how indexicality is maintained or destroyed by post-production. If the development or processing merely enhances qualities like the brightness, contrast, tonality or sharpness of what was recorded, it does not disturb the geometrical mapping essential to indexicality. But if the processing goes further, and profoundly rearranges what was recorded in ways that interfere with or abolish the indexicality, what we finish up with may no longer accurately be called a photograph. To illustrate this, imagine that Leonardo da Vinci has just painted the Mona Lisa. He then chops up

Words by Ian McNab

If post-processing rearrangeswhat was recorded inways that interferewith or abolish indexicality, what we finishwithmayno longer be a photograph

In recent editions of Photography News , both Peter Yeo and Dave Hipperson have mentioned issues for club competitions arising from the wide diversity of digital images now being entered. But these problems are hard to deal with, partly because we no longer talk precisely about what a photograph is. Instead, we use the vague term ‘images’. In the visual arts, some pictures are built up or ‘synthesised’, and the artist has to decide what will appear on every square centimetre of the picture’s surface. Examples of such synthesised pictures are paintings, drawings and collages. Photographs are made by recording on a light- sensitive surface the pattern of light reflected by objects. Commonly this is done by means of a camera that focuses the pattern of light bouncing off objects in front of the lens onto sensitive film or a digital sensor. Thus a photograph is quite different from synthesised pictures. A photograph is more like a brass rubbing: it is a trace or imprint of what is in front of the lens, made on the film or sensor by the patterns of light. And there has to be real stuff in front of the lens for this to happen. You can paint a picture of a unicorn trotting up a rainbow, but you cannot take a photograph of a unicorn trotting up a rainbow; you can make a photomontage of angels issuing forth from the gates of heaven, but you cannot take a photograph of that.

Is Ian McNab on the right track? Should we be categorising images as indexical or synthesised for judging purposes? Share your thoughts with us at WHATDOYOUTHINK? Perhaps a way forward would be to judge synthesised images in their own category. This approach is already being tried (and in some cases monitored via the entrants’ original camera files), for example by RPS, FIAP and some BPE competitions. the painting into tiny squares, and uses them to make a mosaic image of a piazza in Florence. Is the resulting picture of the piazza a painting? Surely we have to say it is not, even though all the little squares were from what was originally a painting. What we have now is, rather, a mosaic: the post-processing has abolished the connectedness of the painted surface that characterised the painting. Similarly, some digital post-processing may entail cutting out sections of a photograph, replacing them with sections from others, adding elements from other photographs or from other digital images by compositing, or adding computer-aided drawing, or software-generated effects. Such transformations abolish the correspondence between the objects in the world and the original ‘traces’ of the light from them that was recorded. The process creates a new, synthesised picture that may perhaps be described as a ‘mixed media digital image’. The digital image created by assembling what was originally photographic material is thus a synthesised picture similar to other ‘non-indexical’ representations, such as drawings. Of course, some artists are deeply fascinated by the process of synthesising visual images using computer software. That kind of artistic endeavour rightly has a place among the visual arts. Other artists may prefer to work in the medium of the indexical photograph. However, a particular problem arises when these different kinds of visual art are judged side by side, and technical clarity, precision of composition and striking visual content are highly regarded qualities. Here, carefully synthesised images made by transforming photographic elements by means of computer software are at a distinct advantage over those made in the less tractable medium of indexical photography with a camera.

LEFT From indexical photograph to synthesised image.

Photography News | Issue 8

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