Page maintained by Dick Suiter

A page that has two articles about designing and making apodizers, devices that reduce diffraction rings around point images, supposedly increasing steadiness and contrast.

The Excel spreadsheet tex8inch.xls is used to analyze the 8-inch mirror in Texereau, with some attention to duplicating the approximate appearance of the Test Data Sheet in Texereau. Note that one difference is the lack of reference parabola. You much change the focus constant by hand (just above the graphs) to achieve minimum wavefront deviation. This is straightforward to do. Just put the reading of the Line 8 reading of the outermost zone in for a first attempt, and then twiddle from there. If you have more or fewer zones, change the number of columns in the sheet. See disclaimer above.

A list of easy things to do to make your telescope better.

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Last updated in Feb 2017