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APEX Blind Deconvolution of Real Hubble Space Telescope Imagery and Other Astronomical Data



Alfred S. Carasso


The APEX method is a non-iterative, single frame, direct blind deconvolution technique that can sharpen certain kinds of high resolution images in quasi real-time. The method is predicated on a restricted class of blurs, in the form of 2D heavy-tailed bell-shaped surfaces. Not all images can be usefully enhanced with the APEX method. Nevertheless, the method is found effective on a broad class of galaxy images, including color Hubble Space Telescope ACS imagery. APEX-detected optical transfer functions that successfully sharpen these images are far from Gaussian, and of a type not commonly found in the astronomical imaging literature. Visually striking enhancements are obtained, with significant sharpening confirmed by better than threefold increases in image gradient norms.
NIST Interagency/Internal Report (NISTIR) - 7283
Report Number


APEX method, astronomical images, blind deconvolution, color imagery, direct method, Hubble Space Telescope, Pinwheel galaxy, Tadpole galaxy, Whirlpool galaxy


Carasso, A. (2005), APEX Blind Deconvolution of Real Hubble Space Telescope Imagery and Other Astronomical Data, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed July 15, 2024)


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Created December 2, 2005, Updated January 27, 2020