Astrophotography by Philipp Salzgeber

Schlieren movie

	This short movie shows the sensitivity of the foucault test. Not only very small errors in the curve of the mirror are visible, even slight temperature differences in the air are clearly visible. Watch the warm air rising from my hand and the warm breath coming out of my mouth and nose.
This movie was taken with the mirror in autocollimation. The flat mirror has a hole, which is visible in this image as the dark center.
Camera:Nikon Coolpix 4500

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