... Laboratoire Signal et Image, Ecole Nationale de Physique de Marseille, Domaine Universitaire de Saint Jerome, 13397 Marseille Cedex 20, France . ... Astronomical ultraviolet images were obtained from a balloon-borne telescope equipped with a photon-counting detector. ... We take advantage of the high temporal resolution available, to significantly reduce, during the image reconstruction process, the blur induced by the residual movements of the guidance system. ... 4) The images are periodic. ...

... A Posteriori Guidance for Astronomical Images P. Melon, M. Guillaume and Ph. ... When pro­ cessed, successive frames are grouped in blocks of the same size (between 1 and 10 frames per block). ... Algorithm Thereafter we consider that an elementary, i.e., a high temporal resolution image, is built from all events included in a block of frames by a simple pile­up of photoevents at their original X­Y address. ... In the algorithm, the only free parameter is the number of frames per block. ...

IRAF/STECF 2-D spectrum point source / background decomposition package . ... The general problem is one of spectral decomposition - of separating the spectra of the point sources from the background. ... The STECF IRAF layered package "specres" provides two tasks to extract point source spectra from 2-D images (either longslit, multislit or cross-dispersed) and decompose the full background over the image. ... A Point Source Function spectrum image is required as a 2-D spectrum. ...