Anisoplanatic Image Restoration at ADFA

We have been investigating ways to restore images of objects obtained with a telescope under anisoplanatic atmospheric conditions. Anisoplanatic means that the point spread function due to atmospheric turbulence is position dependent. We began by looking at extended astronomical objects, such as craters on the moon but have turned our attention to extended objects on the earth's surface imaged in the horizontal direction in daytime. Our method involves two stages — registration to dewarp individual frames and blind deconvolution of the result. Of particular interest is that we have shown that super-resolution may result because of an apparent increase in telescope aperture due to atmospheric turbulence. A spin-off is a visualisation of the turbulence, currently used to examine the wake behind a jet aircraft. We are also investigating a multiconjugate adaptive optics solution to the problem.

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