The Sciopticon manual : explaining lantern projections in general, and the Sciopticon apparatus in particular, including magic lantern attachments, experiments, novelties, colored and photo-transparencies, mechanical movements, etc. (1877)
Marcy, L. J. (Lorenzo J.) · Philadelphia : J.A. Moore · leaf 27
hat the marginal rays of the field of view strike the lens under a larger angle than the central rays, and consequently suffer a greater refraction. Of the simple form Of lenses, the meniscus, with its concave side to the object, shows it the least. But it is best overcome by a combination of… … Mff. 8. "When the ground-glass is placed at a a, only the central part will appear sharp ; when at b b, only the points of the arrow will appear well defined. This error is avoided by combination of lenses with suitable curves, and by stops.
Lantern projection · Slides (Photography)
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.
