aperture stop
Date: 1880-1910
Inventory Number: 2007-1-0517
Classification: Diaphragm
Dimensions:7.7 × 10.1 × 1.4 cm (3 1/16 × 4 × 9/16 in.)
Description:
This is a circular aperture stop for use in a camera or photographic telescope (or astrograph). It is made of a blackened brass plate with two edges bent in opposite directions. There is a screw hole on each of the other two edges.