Diffraction-limited CCD imaging with faint reference stars
نویسنده
چکیده
By selecting short exposure images taken using a CCD with negligible readout noise we obtained essentially diffraction-limited 810 nm images of faint objects using nearby reference stars brighter than I = 16 at a 2.56 m telescope. The FWHM of the isoplanatic patch for the technique is found to be 50 arcseconds, providing ∼20% sky coverage around suitable reference stars.
منابع مشابه
Diffraction-limited 800nm imaging with the 2.56m Nordic Optical Telescope
A quantitative assessment is presented of diffraction-limited stellar images with Strehl ratios of 0.250.30 obtained by selection of short-exposure CCD images of stars brighter than +6m at 810nm with the Nordic
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