[ATM] questions about the condition of this mirror

[Roman Toledo <rtoledo2002@yahoo.com>]

    Hello everyone, I've been working on & off on this mirror for 6 months and
just reached the point where the laser lights is no longer leaving no
difraction on the surface (except for a couple of specks).

     This is a 12.5" by 2" thick Pyrex bought from one of the mirror makers on
one of the Yahoo groups, I posted some pictures here

http://geocities.com/rtoledo2002/

 and have some concerns.  the first 2 pictures titled COC and COC2 are of
course at COC, in it you can see these scratches one in particular looks like a
Y  ,  the back of the mirror came fairly smooth but not polished, you can see
circular tracks in it, from when it was ground, I started polishing  the back
with some 5 micron to see if I could get it smoother and see if the scratches
started to reduce(this needs lots more work and probable start at 600).  the
reason the mirror was sold was because of imperfections and all I saw mentioned
was about 2 small bubles one near the surface the other in the middle and that
it was very well annealed.

   I need some opinions if these scratches appear to you as being on the
surface or showing through from the rear. these pictures where taken in a room
with a lot of turbulance so they are not great.

   I would not mind also hearing what condition the sphere is in, from what
little I know and reading a few pages, it appears to me I have a TDE  and a
hole in the middle.  I got a bit agressive on the edge the last hour of
polishing, as for the center.

  Confesion time, well I did a newbie thing because I was having problems
polishing (due to maintenace issues with the pitch) the middle and used a 50%
tool for 30 minutes in long w strokes to polish out the center(pryor to this
the lines where perfect with no TDE), I did it using black rouge for that 30
minutes but did it using polishing pads which I read go fast but are not so
good on the surface smoothness, I also got a bit agreesive on the last hour on
the edge and this gave me the TDE.

   I intend to polish a lot more to get a smooth surface, and get back to a
sphere and will also polish out the back side until all the circular patterns
are gone.

   let me know what you think and thank you for your opinion
regards
Roman Toledo

regards,
Roman Toledo
Celestron Nexstar GPS 9.25
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