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Determining the gain and readnoise using findgain

  At CTIO it is common to measure the CCD gain and read-noise whenever a CCD is installed on the telescope. Rob Seaman has provided a useful script called findgain that will provide good estimates of the gain and read-noise using two flat-field exposures and two bias frames. The frames should not have been processed or combined in any manner. The astronomer should specify a section of the image over which the flat-field is relatively constant. Additional details can be found by reading the help page for findgain. The routine currently lives in the nproto package.
Tue Feb 14 07:48:00 MST 1995