We're planning to make two things: a painting that's been painted with the help of a photograph, and a photograph that's been printed with the help of a painting. The photograph can help the artist experiment with details of colour and light, and the painting can help drive the tone mapping that you need to print a photograph well. We hope it'll be interesting to see how science can shed some light on perception, and how much photographic printing relies on painterly techniques.
One way of thinking about what it is that a painting does is to consider the problem of lightness range.
The brightest part of a natural scene will be several thousand times brighter than the darkest. In extreme cases, such as between the light level in a crack in a tree trunk and a patch of sky near the sun, the differences can be extraordinary, up to 10 billion to one.
Experiments have shown that the optic nerve carries lightness levels from the eye to the brain coded as a series of pulses. The faster the pulses, the brighter the spot being represented. However, the maximum range of pulse frequencies that the nerve can carry is only about one hundred to one. How is the amazing range of values present in a landscape communicated to the brain?
The answer is adaptation. As your eye tracks around a scene, it constantly adjusts the iris and the retina to keep the signals from the cells at the back of your eye inside the range of possible values. Your eye becomes more sensitive when you look at a darker part of a scene and less senstive when you look at the bright areas
Paint on canvas can also represent about a one hundred to one ratio. A deep black paint will reflect only about one percent of the incoming light, and a spot of white paint will reflect about ninty-five percent. A painting can't represent the range of values found in nature, but it can represent the signal in the optic nerve. Your eye has to adapt as it looks around a natural scene, it does not need to adapt looking over the surface of a painting...
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