ATM RE: Keep Polishing or Back to the old Grind?!

["Bertapelle, Ken" <Bertapelle.Ken@tci.com>]

Adam,

Please clarify your question.  What do you mean by 1/.2 and 
1/.4?  For example, 1/.2 = 1 divided by .2 = 5?  Or, do you
mean 1/.2 = 1 and .2 = 1.2?  Or do you mean something else?

I'm interested in the answer to this too, but I think there
will be some ambiguity in the responses you'll get due to
the way you described your problem.  Thanks.

- KenB

> -----Original Message-----
> From: Adam Rosenberg [mailto:adamr@synopsys.com]
> Sent: Tuesday, July 13, 1999 1:46 PM
> To: atm@shore.net
> Subject: ATM: Keep Polishing or Back to the old Grind?!
> 
> 
> 
> I recently finished polishing and started figuring my first
> mirror(10" F/6).  Initial readings told me that in zone 3 on
> a 5 zone mask I was out by 1/.2 wavelengths.  I've spent about
> 4 hours grinding out the outer half of the mirror to bring it
> down to the hole in the center and now have readings of 1/.4
> in zone 3.
> 
> Here's the question, am I that far out that I'll make better 
> progress going back to say 220 grit or does it make sense to
> put some more hours in figuring this thing.  I've seen too many
> past threads where people spend their life trying to polish out
> something they could have ground out in 8 hours.
> 
> Thanks,
> 
> Adam R.
>