An Improved Automatic Guider
H. W. Babcock, B. H. Rule, J. S. Fassero · Publications of the Astronomical Society of the Pacific · 1956
An experimental model of a photoelectric guider for astronomical telescopes was described some years ago. 1 This guider was employed for holding a star image in a fixed position on the reflecting slit jaws of the coudé spectrograph of the 100-inch telescope.It employed a rotating knife-edge and a multiplier phototube for sensing deviations of the image from the desired