A dictionary of photography for the amateur and professional photographer (1889)
Wall, E. J. (Edward John), 1860-1928 · New York : E. & H.T. Anthony · leaf 110
DICTIONARY OF PHOTOGRAPHY. IOO discovered, and from this origin all lenses of the present day have been evolved. All lenses are made of crown or flint glass^ the former being free from and the latter containing lead, being slightly more refractive than the former. The sectional forms of the various… … d e f Fig. x.— a, double convex; b> plano-convex; c, concavo-convex or converging meniscus ; d, double concave ; e> plano-concare j f, divergent meniscus. The first three, a, b} ct which are thicker at the centre than at the margins, are convergent or positive ; and the second three, d} e, f, are…
Photography
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.
