Three College Observatory

A 1K x 1K ccd camera is used for research projects on the 0.81-meter telescope. The camera uses a Texas Instruments TC215 chip cooled with liquid nitrogen to approximately -100 degrees Celsius.

The camera was constructed in 1994 by First Magnitude Corporation, Laramie, Wyoming. Pixel size is 12 microns square. At the Cassegrain focus of the 0.81-meter telescope this corresponds to a pixel size of 0.23 arcseconds on a side. On-camera binning can produce pixels of 0.46 arcseconds on a side. Using all 1024 pixels the image size is thus 3.86 arc minutes on a side.5

Estimated camera readout noise is about 20 electrons with an estimated dark current of less than 0.1 electrons/second. Images are produced in fits format using windows software operating on a 486sx computer at the observatory. The camera is equipped with UBVRI filters.

The quantum efficiency of the camera is approximately 40% in the B passband, approximately 50% in the V passband, and peaks at approximately 70% in the near infrared at about 7000 Angstroms.