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Cleaning Mirrors

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#1 StarWars

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Posted 26 May 2004 - 12:29 PM



When cleaning a mirror use a cleaner which will completely evaporate...

All mirrors MUST have a protective coating!

If the mirror did not have a protective coating the reflective aluminum dust coating will oxidize and would loose it's reflectivity...a compact disc (CD) also utilizes the same type of technology..

#2 Levente

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Posted 31 May 2004 - 01:28 PM

My question is simple: does the primary mirror of the Celestron 8 have protective coating on the surface?

#3 John Hoare

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Posted 31 May 2004 - 01:42 PM

All primaries need a protective coating to prevent oxidization. I don't know for absolute certain the answer to your specific question but I'd be totally astonished if it's 'no' given the reputation of C8s.

#4 bierbelly

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Posted 31 May 2004 - 03:49 PM

Even the mirror of my MakNewt, made in the early 1960's had a protective coating on it. I'd be pretty certain that they all do.

#5 Don W

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Posted 31 May 2004 - 04:13 PM

Yes, any aluminized surface has to have an overcoat. Otherwise it oxidizes very rapidly.

#6 StarWars

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Posted 03 June 2004 - 01:47 AM

My question is simple: does the primary mirror of the Celestron 8 have protective coating on the surface?



Good question...the mirror will have a protective coating however not sure which type of materials are used in the process..

#7 Don W

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Posted 03 June 2004 - 07:07 PM

Usually it's silicon oxide (SiO), but they can add other more expensive coatings that have higher reflectivity.


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