Study on Field of Rotation of 1.2m Alt-Az Telescopeand Elimination of Image-Rotation

In this paper, the characteristic of movement of the 1.2m Alt-Az telescope is discussed briefly. The quantitative analysis of formula for the object field rotation is presented, and the quantity and the direction of the image field rotation is determined. Three methods of eliminated rotation are compared, and the conclusion that the physical eliminated rotation is more suitable for 1.2m Alt-Az telescope is drawn. Finally, the eliminated rotation control system's structure is introduced.