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.

This is a long paper with some speculations about Galileo's telescope making. It also is a tutorial on Galilean telescopes and discusses building of a simulated "small" telescope of Galileo himself.

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. You may use it to analyze your own mirrors, but like all spreadsheets, it is dangerous to everyone but the people who wrote it (and somewhat dangerous even to them). I make no guarantees.

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

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Last updated in Nov 2017