To perform imaging observations of optically red objects such as high redshift quasars and brown dwarfs, the Center for the Exploration of the Origin of the Universe (CEOU) recently developed an optical CCD camera, Camera for QUasars in EArly uNiverse (CQUEAN), which is sensitive at 0.7-1.1 μm. To enable observations with long exposures, we develop an auto-guiding system for CQUEAN. This system consists of an off-axis mirror, a baffle, a CCD camera, a motor and a differential decelerator. To increase the number of available guiding stars, we design a rotating mechanism for the off-axis guiding camera. The guiding field can be scanned along the 10 arcmin ring offset from the optical axis of the telescope. Combined with the auto-guiding software of the McDonald Observatory, we confirm that a stable image can be obtained with an exposure time as long as 1200 seconds.

• SooJong Pak(School of Space Research, Kyung Hee University)
• MyungShin Im(CEOU/Dept. of Physics and Astronomy, Seoul National University)
• SeungHyuk Chang(Samsung Electronics)
• Peter S. Odoms(McDonald Observatory, Univ. of Texas at Austin)
• Han Geun Kim(Department of Electrical Engineering, Kyung Hee University)
• Dong Han Kim(Department of Electrical Engineering, Kyung Hee University)
• John Kuehne(McDonald Observatory, Univ. of Texas at Austin)
• JinYoung Kim(School of Space Research, Kyung Hee University)
• HyeonJu Jeong(School of Space Research, Kyung Hee University)
• Won-Kee Park(CEOU/Dept. of Physics and Astronomy, Seoul National University)
• EunBin Kim(School of Space Research, Kyung Hee University)