![](http://www.alamy.com/thumbs/6/BB72A290-14EE-4653-A8E5-636E19E06713/2RC4M5Y.jpg)
Optical chart NUMBER 836 illustrates the focal length required to capture different angles on photographic plates in war industries. Example No. 8 demonstrates that a diagonal of an 11x14 plate requires a focal length of 9 inches. The chart provides focal lengths for various plate sizes, ranging from 4x5 to 20x24 inches.
Size: 9182px × 6304px
Photo credit: © piemags/NSC / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., 10x12, 11, 11x14, 14, 14x17, 16x20, 8, , 18, 18x22, 1919, 20x24, 24x36, 3x4, 4x5, 5x7, 5x9, 6x9, 7x9, 8x10, activities, administration, american, angle, au, chart, charts, diagonal, fine, focal, horizontal, inches, indust, industries, length, line, military, optical, photographs, plate, protoper, rec, required, secal, size, slate, symbol, tetrary, vertical, view, war, world