Historical information
Training and eductation
Physical description
Stereometer parallax bar in wooden case. This instrument is comprised of two glass plate holders mounted on a centerless-ground, stainless-steel bar. A precision micrometer is attached by four screws to the end of the bar on the right hand side.
Inscriptions & markings
Parallax Bar. Designed and Constructed by E.Esdaile & Sons, Sydney. Property Victorian School of Forestry, Forests Commission, Victoria
References
- Description and history at Powerhouse Museum The bar is used to determine the height difference of natural and man made features when viewing stereoscopic photographs. It measures the relative position of identical points in both photographs, that is their parallax difference. The parallax difference can then be used to compare the relative heights.