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Schmidt telescope PSF.svg Schmidttelescope PSF UTC Schmidttelescope PSF Pearson Scott Foresman derivative work Malyszkz talk Zwektoryzowano Krzysztof Zajczkowski malyszkz Schmidttelescope PSF PDScottForesman Original upload log This image is derivative work of the following images File Schmidttelescope PSF with PDScottForesman