Size of Image as a Guide to Depth of Focus in Cinematography

J. F. Westerberg

The questions discussed in this paper are: (1) The depth of focus vs. depth of field. (2) The size of the permissible circle of confusion. Should it be a constant value or should it vary as in still photography? It is concluded that it should remain fixed. (3) Magnification as an index to depth. The simple rule that depth varies inversely as the square of the magnification may prove to be a very practical yardstick in the appraisal of depth in the photographing of near-by objects. A table is shown in which the magnification is estimated from the size of the figures on the ground glass. The corresponding depth is given for various stops.

Print ISSN
Published
1932-05
Content type
Original Research
DOI
10.5594/J05533