Re: 1/6 or 1/8 wave

RMOLLISE wrote:
Hi:

1. That's his opinon.

Hi Rod,

While you are correct that it is his opinion it is also true that in the course of polishing a mirror heat is generated. That heat changes the mirrors figure slightly. So it becomes problematic to get a good surface without altering the figure. A rather decent glass pusher once told me that he would work a rough zone/high spot by warming that spot with his hand prior to working it.


It should also be noted that these are not spherical, or parabolic mirrors.


2, The Deluxe scopes didn't _use_ Pyrex.

Indeed.


Regards

Bill

PS: The last time I spoke to R.R. about a large mirror he couldn't provide a zero expansion one due to problems in getting the blanks.
.

Relevant Pages

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  • Re: Formatting [was: Re: Grammar Crackdown]
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  • Re: Formatting [was: Re: Grammar Crackdown]
    ... Have you considered sending the mirror off for re-silvering? ... the time that the paraboloid was finally formed. ... the mirror tested to near-perfect before polishing was complete. ... I was happy with the resulting telescope and mount until the telescope ...
    (alt.usage.english)
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  • Re: Formatting [was: Re: Grammar Crackdown]
    ... the time that the paraboloid was finally formed. ... the mirror tested to near-perfect before polishing was complete. ... I was happy with the resulting telescope and mount until the telescope ...
    (alt.usage.english)