aerial perspective

aerial perspective. Term describing the means of producing a feeling of distance in a painting by imitating the effect of atmosphere whereby objects look paler and bluer the further away they are from the viewer. Dust and large moisture particles in the atmosphere cause some scattering of light as it passes through them, the amount of scattering depending on the wavelength (hence colour) of the light. Short wavelength (blue) light is scattered most and long wavelength (red) is scattered least. This is the reason why the sky is blue and why distant dark objects appear to lie behind a veil of blue.

The term ‘aerial perspective’ (‘prospettiva aerea’) was invented by Leonardo, but the device was used much earlier by Roman painters, for example at Pompeii. In the work of Italian painters of Leonardo's time, backgrounds sometimes look artificially blue, and in general aerial perspective has been more subtly exploited in northern Europe, where the atmosphere tends to be hazier. No one used it more beautifully than Turner, in some of whose late works it is virtually the subject of the painting.