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RE: RE: ??How Thick Should I Go??

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Posted by X might mark the spot but... on May 6, 2000 16:15:15 UTC

it is no guarantee you will not have astigmatism. You forgot to mention that the "X" should disappear evenly, the fact that it dissapears means nothing as per ATM Vol 1-3. Also it is no guarantee that when you place the mirror into its mounting cell that it won`t have astigmatism. The blanks you mention certainly are not in the same category of "thin" as the inquirer`s 10" x 3/4"T.I know some folks have made thinner ratio mirrors using 27-36 point flotation but even then they also had twice or more thickness to transmute local loads from mounting points. I an not inclined to recommend this thin a mirror for a first project. Instead shop the Astromart or Ebay for a good blank if you can wait or shop for one from the commercial vendors. Newport by far is not the least expensive but may have just what you want.

Good Luck,
-Rick

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