Re: ATM HELP! mirror making crossroads

["Bob May" <bobmay@nethere.com>]

Actually, the mirrors made in the Dobson tradition are more like the Coulter
mirrors of old.  You sometimes get a good one and sometimes you get a bad
one.  The method that John uses can indeed produce a good mirror but often
fails but that really doesn't mean much because his instruments really
aren't for getting the maximum amount of light into an Airy disk but to get
some magnification so that the fainter things can be seen in the sky.  So
what if the stars are a bit larger than they really should be, the average
person won't be able to tell the difference in the first place and the
uneducated public thinks that is the way that they should be.  They don't
care about getting the last half magnitude in a star and the idea of a
cluster being a bunch of sharp pinpoints is foreign to them.  Just seeing
the outer stars as points is amazing for the average viewer.
In other words, if you want a light bucket, the Dobson method of grinding
and polishing is just fine!
Bob May
http://nav.to/bobmay
bobmay@nethere.com
NEW! http://bobmay.astronomy.net