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Spectrum Coating Options

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#1 AXAF

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Posted 21 November 2012 - 08:24 AM

Hi all:

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.

Gary

#2 Mirzam

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Posted 21 November 2012 - 10:33 AM

Your mirror would not have to travel as far if you sent it to Majestic Coatings in New Jersey. They do not use edge clips.

JimC

#3 Jarad

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Posted 21 November 2012 - 10:35 AM

I have it on a 14.7" mirror. No clip marks on that mirror, and the coating seems quite good. I've had it for about 2 years, no visible degradation so far.

Thanks,

Jarad

#4 FirstSight

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Posted 21 November 2012 - 02:02 PM

I have the "R"© EAL coatings by Spectrum on my 12" dob, and was pleased with both the promptness and quality of service and work by Spectrum. Paul was reasoably accessible by phone to discuss the options for coatings. Yes I'd use Spectrum again.

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.






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