From: "Aditya Munshi" 
To: 
Reply-To: "Aditya Munshi" 


Hi everyone

I am figuring my 8" f/7 mirror which had a severe TUE (ROC diff 10 mm)
and a central hole. When I attempted TUE correction with a TOT Chordal
Stroke it created a severe surface irregularity ( I could see 6 small
depressions arranged in a circle around the centre in the Foucault test).
However I have come a long way since then, hot pressing and polishing out
defects with only slight variations in stroke length. The Central hole is
nearly gone and the TUE ROC diff is about 2 mm. The problem is that the
surface irregularity has also disappeared with about 4 hours of MOT and TOT
work. The surface is pretty smooth as a whole but I can just spot the 6
depressions in the Foucault test. As a next step I will probably try
micro-faceting and slow gentle polishing but any help is greatly
appreciated.

The irregularity is very minor as compared to the previous figure but still
I think it would be best to iron out all visible defects.

Thanks for any help

Aditya Munshi

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