|Overall Size:|| 4.0 in. x 4.0 in. |
(101.4mm x 101.4mm)
|Resolution:|| 0.48 to 3.20 cy/mm|
|Based on:|| NBS Circular 533-1953|
The NBS-1952 Resolution Test Chart is described in the NBS circular 533-1953 in the section “Method of Determining the Resolution Power of Photographic Lenses". Design features of this target reduce edge effects, minimize spurious resolution and permit one pass scanning.
The NBS method of using this chart to test lenses involves placing the chart at a distance from the lens equal to 26 times the focal length of the lens, resulting in a 25x reduction. The reduction effective cycles per mm is 12 to 80 c/mm.