Spectrum Coating Options
Posted 21 November 2012 - 08:24 AM
It's time to recoat my 12" mirror, and am thinking of sending it down to Spectrum Coatings. Out of curiosity, I see that Paul offers a coating product called "R"© EAL, which is supposed to be highly efficient and uniform over the visible band. Has anyone had personal experience with this one? It definitely sounds like the way to go.
The other question I have, is I know that some coating systems mount the mirrors in the chambers with clips, such that the edge of the mirror, in a few spots, can be devoid of the coating. Does a Spectrum Mirror coating cover the entire surface?
Thanks and regards.
Posted 21 November 2012 - 10:33 AM
Posted 21 November 2012 - 10:35 AM
Posted 21 November 2012 - 02:02 PM
There were no coating-clip marks on my mirror either when I got it back from Spectrum. However, intermittent contact by the mirror with even well-adjusted mirror cell clips in my scope eventually causes a noticeable wear mark on the coatings that somewhat mimics coating clip-marks when I take the mirror out of its cell for an occasional light rinse with distilled water. For that reason, when returning the mirror to its cell afterward, I make sure the mirror is in the same orientation relative to the clips so the wear-marks are hidden underneath the overhang of the clips.