From: "Bob May" 
To: "atmlist" 
Reply-To: "Bob May" 


The changing of the masks is easy as they are just set in front of the
mirror on the pegs of the mirror holder.  A light touch on the posterboard
pulling it away from the top of the mirror and it falls off very nicely
(sometimes, a mask wants to fall off anyway!) and a new mask is easily set
on the pegs without problems.
From my experience, there is so little force on the mirror stand that the
shadow on the mirror hardly changes while the forces are put on the mirror
stand while changing the masks.
If you are really paranoid about this, make up a support for the masks in
front of the mirror (you don't have to have the mask right against the
mirror but can put it even an inch, or so, in front of the mirror!) and
that will insure that you don't touch the mirror while changing the masks. 
Also the idea of making the masks selfstanding and putting a shelf in front
will also work nicely.
Bob May
http://nav.to/bobmay
bobmay{at}nethere.com
NEW! http://bobmay.astronomy.net

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