Zone System and L values

2011-10-18

Zone System is defined in terms of 11 zones. In practice I process my photos in Darktable and work with lightness values ranged from 0 to 100. Knowing correspondence between Lightness values and zones is useful, because it gives a good starting point when I decide how light or dark the subject should be.

This is the zone scale translated into lightness values:

Zone Lightness Texture range Description
0 0–9 Pure black
I 9–18 Near black, with slight tonality but no texture
II 18–27 Textured black; the darkest part of the image in which slight detail is recorded
III 27–36 Average dark materials and low values showing adequate texture
IV 36–45 Average dark foliage, dark stone, or landscape shadows
V 45–55 Middle gray: clear north sky; dark skin, average weathered wood
VI 55–64 Average Caucasian skin; light stone; shadows on snow in sunlit landscapes
VII 64–73 Very light skin; shadows in snow with acute side lighting
VIII 73–82 Lightest tone with texture: textured snow
IX 82-91 Slight tone without texture; glaring snow
X 91–100 Pure white: light sources and specular reflections

Hence, “dynamic range” is L=[9,91] and “texture range” is L=[18,82].