Handbook of the practice and art of photography (1875)
Vogel, Hermann Wilhelm, 1834-1898, Molling, Edward F · Philadelphia, Benerman & Wilson · leaf 71
65 ANGLE OF VIEW, ETC. The term depth of focus denotes the capability of giving in the same plane an image of objects near and far. With objects which are fur- ther removed from the camera than fifty times the length of the focus of the lens, this is, eo ipso, the case; the images in this case are… … from the lens. If therefore objects which are very near and very far from the lens are to be represented at the same time, we cannot focus on them simultaneously with the full opening of the lens. If we Fig. 43. focus on the further one at / (Fig. 43), the nearer one, the focus of which is atp,…
Photography
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.
