Fringing in CCD images is troublesome from the aspect of photometric qualityand image flatness in the final reduced product. Additionally, defringingduring calibration requires the inefficient use of time during the night tocollect and produce a "supersky" fringe frame. The fringe pattern observed in aCCD image for a given near-IR filter is dominated by small thickness variationsacross the detector with a second order effect caused by the wavelength extentof the emission lines within the bandpass which produce the interferencepattern. We show that essentially any set of emission lines which generallymatch the wavelength coverage of the night sky emission lines within a bandpasswill produce an identical fringe pattern. We present an easy, inexpensive, andefficient method which uses a neon lamp as a flat field source and produceshigh S/N fringe frames to use for defringing an image during the calibrationprocess.
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