Precision Astronomical Photometry using Large Image Sets

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Near Los Alamos, New Mexico, Dr. John Farrell studies variable stars using Mira Pro 7 to do precision aperture photometry on large sets of CCD images. Dr. Farrell is a physicist who wants to focus on science rather than on how to stay awake all night or how to tediously grind through 100's of images the next day. Yet his work requires the type of processing sophistication that astronomers usually associate with the "one image at a time" method. One of his recent results is illustrated at left, in his light curve for the dwarf Cepheid variable star, BL Camelopardalis.

Dr. Farrell uses a cocktail of Mira Pro 7 for image processing with other software for camera and telescope control to produce high-precision results in a relatively automated fashion. At left, a processed CCD frame centered on BL Cam is displayed in a Mira image window. The light curve shown above used 85 CCD frames like this, each of 120s exposure time, acquired on a night of variable "seeing" (i.e., turbulent atmosphere).