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    Re: Whole mirror or Traditional? you make the call!
    From: Bill B
    Date: 2006 Apr 1, 20:46 -0500

    > Defend your position, and is it easy to swap mirrors?
    Rather than quote my sources verbatim, read the opinions of Ken Gebhart and
    David Burch online:
    The gist is some light is lost (not reflected) by a two-way mirror.  Making
    horizons and stars harder to distinguish at twilight.  The blue cast can
    also make horizons harder to distinguish in less-than-ideal conditions.
    As the owner of Celestaire, Ken has well-established credentials as a pilot
    and navigator using cel nav.   David is also well respected and has his own
    As to my opinion of Celestaire's business practices, it is based on many
    dealings.  If there was a mistake made no argument, they take care of it
    pronto--no beating around the bush. Never an argument of "small print"
    As to buying new, it would appear that all the Astra IIIB models now come
    standard with what was the "deluxe" index mirror (front silvered).  It was a
    $40 option.  So at $400 for a used unit without a front silvered index
    mirror, you are probably paying about what the seller paid for the unit when
    >and is it easy to swap mirrors?
    If you just swap out mirrors in the frame, it could be a bit painful,
    especially as you would have to go back and forth adjusting index error and
    side error every swap.
    You can purchase a mirror in frame for the Astra for a few sawbucks more
    than the mirror alone (approx. $70 in frame).  Then it is a breeze.  Just
    remove two screws, replace it with the other frame/mirror, and replace the
    screws.  Ken suggested that one should barely snug up the screws, and wiggle
    the frame around until index error is minimal, then finish tightening the
    screws.  That's all there is to it.  If side error was already adjusted
    once, you should not have to mess with again.
    Hope that helps,

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