Uses of Photography

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Uses of Photography

Many people think of photographs as the touchstone of
reality for static mages. But this idea is a source of real confusion.

The method outlined here offers one of many ways of thinking
about differences between a photograph and human perception.
It argues that painting can represent some aspects of vision
more easily than photography, and with greater aesthetic impact.

1.Revealing colour-textures

I wanted to paint a cornfield panorama facing the morning sun on one side and
looking away on the other. There were very dramatic changes of light and colour
across the field and I used digital photography to help me organise the colours.

I made oil studies of colours across 120 degrees. I also took photos
with different exposures for different parts of the scene, short towards the sun,
longest away, mimicking the adaption of my eye.

Summeroilstudy1

Oil study of bands of shifting colours in wheat as you look towards (left)
and away (right) from the sun.

Example shots of different parts of the scene, left matches left of oil study, right right.

For many reasons, the colour matches between paintings and photos was imperfect. But they were good enough to suggest that mapping tones from the oil study to similar tones in the photos would help to show the complex distribution of colours painted in the oil study.

Analysing colour distributions in a digital image has been made easy by image processing software. I used an early edition of Adobe Photo Shop to pick colours that were closest to those in the oil studies. These were then displayed against plain background to make them easy to see.

To the left are two different colour selections from the same photograph. I discovered that each colour made a texture and that each texture was subtly different. There seemed to be a natural association of colour with texture, and I started to think of selections as colour-textures.

It turns out that recent work in experimental psychology suggests the existence of a colour-texture association in the visual processing pathway.

references

• Texture interactions determine perceived contrast. Charles Chubb, George Sperling, & Joshua A. Solomon Proc. Natl. Acad. Sci. USA Vol. 86, pp. 9631-9635, December 1989Contributed by George Sperling, August 24, 1989 *

• Color appearance depends on the variance of surround colors Richard O. Brown and Donald I.A. MacLeod. Published: 17 October 1997 Current Biology 1997, 7:844-849 *

If what these papers suggest is correct I don't feel it would be surprising, because primate eyes evolved in a world with almost no simple, regular geometrical objects. There are no rectangles and tramlines inside a wild forest. Go and look for yourself: it's no place for Brunelleschi!

So a history of realism in art that emphasises the development of linear perspective is unbalanced in terms of dealing with the kinds of visual information that are most fundamental to seeing in natural enviroments. Of course there is no obvious reason why a history of art should marry with an evolutionary account of vision - but what if it tried to?

The next step was to apply these distributions to a large oil painting. My idea was to map each selection (called 'layers' in the software) to a paint layer. This exploits a parallel between the basic building block of classical wet-on-dry oil technique and digital image processing. I have been developing this relationship in the studio, and now almost think in colour-textures. I also find it easier to see colour textures within the natural enviroment.

Examples of oil paint layers:

Some differences between painting and photography

Compare a photographic source with a similar area in the painting below. Key differences between painting and photography emerge.

The photograph has thousands of colours. We tend to make sense of this kind of scene by latching onto objects and groups of objects, and perhaps by noticing the illumination. But the scene is hard to see.

But the painting has a limited number of colours, distributed as colour-textures.

This not only of makes the scene easier to see, but also draws attention to the colours themselves. In philosophical terms, there is mutual support and interplay between the cognitive and the aesthetic. Put another way, we are made to feel we understand what we see by our own organisation of seeing.

Because we can sense that each colour is a separate material mark, the paint itself is at work. Further enhancement comes through the contrast of smooth, filmy areas and thick lumpy ones - a classic resource of oil painting.

I now want to bring this method of seeing colour-textures to the apparently less colourful, more elusive subject of water.

Water examples and other uses of photography, including HDR (high dynamic range) and selection tool refinements, will be posted as the project develops.

• Method first published in the catalogue for "Stephen Taylor, New Paintings" , May 2002, The Arts Center, King's College Cambridge. Edited by David Davies, one time editor of the science journal Nature.

* I owe these references to Professor John Mollon of Gonville and Caius College, Cambridge. John has a special interest in the history of primate vision.

Final painting. The sun is directly above the oak tree to the left. For a zoom version click here.