An introduction to the study of colour vision (1915)
Parsons, John Herbert, Sir, 1868-1957 · Cambridge University Press · leaf 85
SCOTOPIA OR TWILIGHT VISION 65 and other luminosity curves. With 0'2 foot-candle of parafoveal illumination the curve is the luminosity curve of the photopic eye. 6 "ft bandies Candle*^, ^003/zs C«j£^ ■00078 \p " — «^„i y i D fLi Extinct, 1 1 24 28 32 36 44 40 46 52 60 56 Fig. 22. " Extinction of… … Fig. 23. " Persistency of light " curves corresponding to the " extinction of light " curves for different degrees of light adaptation. Abscissae, wave-lengths ; ordinates, reciprocals of extinction values. (Abney.) As the parafoveal illumination diminishes the curve shifts towards the violet end,…
Color vision
Internet Archive · Gerstein - University of Toronto · Public domain (published before 1931). Free to use for anything.
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