An automatic photoelectric triggering mechanism for a data-recording camera
By: by W.Y. Pong, R.M. Bass, and H.D. Claxton.
Contributors: Bass, R. M.; Claxton, H. Dean.; Sandberg, David V., 1944-; Pacific Northwest Forest and Range Experiment Station (Portland, Or.)
Series: USDA Forest Service research notes PNW -- 122.; Research note PNW -- 122.
Publisher: U.S. Dept. of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station
Published: 1970
Place of publication: [Portland, Or.]
Language: eng
Number of pages: 11
Subjects: Lumber -- Grading; Electric eye cameras
Notes: Cover title.

"July 1970."