RE: [ATM] ATM Edmund secondary mirrors - worth it?

["Jerry" <wa4guu@verizon.net>]

	What good is a certification? If they advertise 1/12 wave and it is
not a certification does not make it so. Sounds like a lot of money for a
piece of paper that probably won't be a part of the telescope.

	I suspect that you would not be able to tell a difference looking
through the scope. But, ASSUMING that both are measured the in the same way,
1/12 wave is "better" than 1/8 wave. Naturally, just about everyone will
choose "better" until the price enters into the decision. Then it becomes
how much the difference is worth to you.

	If price is not a concern the answer is easier.
Jerry
 

-----Original Message-----
From: John Lynch


<snipped>.................................. In addition, the
Pyrex secondaries are certified to the accuracy stated
($75.00) and if you purchase the ULS Quartz ($137.50),
they'll provide you with an analysis of the secondary
(interferogram)<<<<<<<<<<

John Lynch

--- Gil McFarlane <gilboastro@yahoo.com> wrote:
> In looking for a 1.8"  secondary for a flex mirror
> scope, I found that Edmund has some on sale: $46 -
> but
> nothing is a bargain if it doesn't work well.  Any
> thoughts versus antares or protostar for about $75? 
> 
> 
> Is it possible to see the difference between a 1.8
> and
> a 1/12 wave optic?
> 
> Are these measurements valid?
> 
> Thanks,
> 
> - Gil
> 



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