Dodging and burning

Dodging and burning are terms used in photography for a technique used during the printing process to manipulate the exposure of a selected area(s) on a photographic print, deviating from the rest of the image's exposure. In a darkroom print from a film negative, dodging decreases the exposure for areas of the print that the photographer wishes to be lighter, while burning increases the exposure to areas of the print that should be darker.

Any material with varying degrees of opacity may be used, as preferred, to cover and/or obscure the desired area for burning or dodging. One may use a transparency with text, designs, patterns, a stencil, or a completely opaque material shaped according to the desired area of burning/dodging.

Many modern digital image editing programs have "dodge" and "burn" tools that mimic the effect on digital images.

A key application of dodging and burning is to improve contrast (tonal reproduction) in film print-making; today this is better known as tone mapping in digital photography – see high dynamic range imaging. The technical issue is that natural scenes have higher dynamic range (ratio of light to dark) than can be captured by film, which in turn is greater than can be reproduced in prints. Compressing this high dynamic range into a print either requires uniformly decreasing contrast (making tones closer together) or carefully printing different parts of an image differently so that each retains the maximum contrast – in this latter dodging and burning is a key tool.

An excellent example is the photograph "Schweitzer at the Lamp" by W. Eugene Smith, from his 1954 photo essay A Man of Mercy on Dr. Albert Schweitzer and his humanitarian work in French Equatorial Africa. The image took 5 days to produce, in order to reproduce the tonal range of the scene, which ranges from a bright lamp (relative to the scene) to dark shadow.

Ansel Adams elevated dodging and burning to an art form. Many of his famous prints were manipulated in the darkroom with these two techniques. Adams wrote a comprehensive book on producing prints called The Print (Adams 1995), which features dodging and burning prominently, in the context of his Zone System.

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