The 30-inch Reflector

The telescope was built by Boller and Chivens, Inc. Pasadena, CA. It has a Cassegrain optical system (f/13.5) consisting of two curved mirrors which collect and focus starlight. Located at the lower end of the tube the concave primary mirror is 30-inches in diameter and weighs 300 pounds. It reflects incoming light to the 8-3/16-inch secondary mirror located inside the telescope near the upper end. The light is then reflected through a 7-1/2-inch hole in the main mirror to the focal point at the back of the telescope. Stars in any part of the sky can be viewed by swinging the telescope about the polar and declination axes. Once pointed at a celestial object, it is automatically driven to follow the star across the sky during the course of the night. The domed roof rotates so as to bring the opening in front of the telescope. The observing system has consisted of a TI4849, 390 by 584 pixel, cryogenically cooled CCD detector. The field of view was 2.9 by 4.3 arc minutes, with a scale of 0.44 arcseconds per pixel. We are presently in the process of developing an observing system around a newly purchased SBIG ST-7.

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