We have investigated the astronomical observational environments at the Choejung-san GEODSS site which is located at the south of Taegu, Korea. As a part of the investigation, seeing and night sky brightness were measured outside nearby the GEODSS site using the Celestron 8-inch portable reflector with $192{\times}165$ pixels Lynxx CCD camera during the period of December 1994 to April 1996. The average seeing values of 4.8 arcsecond in B filter and 5.1 arcsecond in V filter were determined using the IRAF software. These values might be overestimated and would be reduced by at least 1 arc second in both filters if they were measured by more stable telescope system with solid mount and under a dome. We also compare the average seeing value at the GEODSS site with those at three other observatories, the Bohyunsan Optical Astronomy Observatory, the Sobaeksan Optical Astronomy Observatory, and the Seoul National University Observatory, for justification of the above guess. Unfortunately the night sky brightness measurement was not successful mainly due to the short exposure time. The utilizing plan of the GEOSS site is discussed based on the average seeing value, naked-eye sky brightness measurement, analysis of the existing thirty-year weather data and twenty-year urban planning of the metropolitan Taegu city for the year of 2016.

The development of universal CCD camera control software for all BOAO CCD camera systems is proposed. The new software, running under Sun SPARCstation and motif based X window system with SunOS 4.1.3 operating system, replaces existing control software based on NeXTstation color and NeXTstep 2.1 operating system which is no more produced now. Several new features of the new software is introduced, some of which are 1) the image contrast is enhanced by color manipulation and display, 2) image zooming and trimming, 3) any size of image can be displayed in the scrolled window, and 4) the offset between telescope pointing position and CCD center is easily calculated by alt-azi map. Along with the above new features, the new software has advantages including ease of maintenance and upgrading and elimination of risk caused by hardware damage. Since September 1, the software beta version is being used by observers and there is not seen severe problem regarding the software itself, but several requests to equip more features to the software will be mirrored to future release.

An introduction to the first CCD camera system in Bohyunsan Optica1 Astronomy Observatory(CCD#l) is presented. The CCD camera adopts modular dewar design of IfA(Institute for Astronomy at Hawaii University) and SDSU(San Diego State University) general purpose CCD controller. The user interface is based on IfA design of easy-to-use QUI program running on the NeXT workstation. The characteristics of the CCD#l including Gain, Charge Transfer Efficiency, rms Read-Out Noise, Linearity and Dynamic range is tested and discussed. The CCD#l shows 6.4 electrons RON and gain of 3.49 electrons per ADU, and the optimization resulted in about 27 seconds readout time guaranteeing charge transfer efficiency of 0.99999 for both direction. Linearity test shows that non-linear coefficient is 6×10−7 6×10−7 in the range of 0 to 30,000 ADU.