The science and practice of photography : an elementary textbook on the scientific theory and a laboratory manual (1920)
Roebuck, John R. (John Ransom), 1876-1965 · New York ; London : D. Appleton and company · leaf 179
LENSES 151 a lens image an imperfect copy of the original. They are Spherical aberration and coma, Chromatic aberration, Curvature of field. Astigmatism, Distortion, Flare, Unequal illumination. … 96. The most serious, since the most difficult to correct, is spherical aberration. It causes a blur- ring of the image and the explanation is best made in terms of the diagram Fig. 29. The rays of light near the edge of the lens are brought to a focus usually nearer to the lens than the rays pass-…
Photography
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.
