Re: [ATM] Not quite immaculate

["Vladimir Galogaza" <vladimir.galogaza1@zg.t-com.hr>]

Pete

> The
>several readings taken between these axes are comparable, except for
>this one spot that reads 1/3.9 or so.  The bad spot is narrow; it
>shows a buggered edge; I wonder how I did it.

>....  I'm after, the guesses of
>experienced mirrormakers

My point was that guessing is unproductive without relevant data
to support it. I am not experienced mirrormaker but my following guess
is equally fruitless as anybodies else. It goes like this:

You can have bad narrow spot by holding the mirror at this spot, or keeping 
your
finger at it causing local heating and consequently swelling of  the surface 
at this spot.
Subsequent figuring will polish off this spot and you will end with
kind of hole at this place. This is not pure imagination because it was
excellently documented by Dale Eason. He showed  how local heating
of the surface by finger touch can be demonstrated interferometricaly.
His images are available.

Regards
Vladimir. 

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