An introduction to the study of colour vision (1915)
Parsons, John Herbert, Sir, 1868-1957 · Cambridge University Press · leaf 100
each quarter of the area is thus equivalent to a quarter of the intensity of light. Any aperture subtending more than 5° will give the same field. Guillery1 confirmed Hess's results by using the size of the area stimulated as a guide to the size of the colour fields. For each colour a gradual… … Aperture in powers of - Z ) limits of the fields -) and nasal (- Fig. 33. The temporal ( of vision for four spectral colours for different areas of stimulation. (Abne}^.) The general threshold of light at the periphery is difficult to measure. Abney used a small spot of luminous paint for fixation.…
Color vision
Internet Archive · Gerstein - University of Toronto · Public domain (published before 1931). Free to use for anything.
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