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Date: 07 Jul 2007 12:40:39
From: Phil
Subject: Damaged mirror
I posted some photos in the alt.binaries.picture.astro newsgroup of the
damaged done to my 17.5 inch mirror during shipping from the supplier.
Thank god there was insurance on the goods.

Phil






 
Date: 09 Jul 2007 00:03:10
From: IMPEACH BUSH NOW!
Subject: Re: Damaged mirror
so poster, who was the maker, who was the shipper, and WHY!?
do you hype the loss and the grief if you dont want to share basic info?
What in hell are WE supposed to DO about it? You want
support or not? Or just a rant?



Phil wrote:

> I posted some photos in the alt.binaries.picture.astro newsgroup of the
> damaged done to my 17.5 inch mirror during shipping from the supplier.
> Thank god there was insurance on the goods.
>
> Phil



 
Date: 08 Jul 2007 21:41:31
From: Dennis Allen
Subject: Re: Damaged mirror
Had a similar situation. A 24" Cervit mirror done by Tom Waineo (he did
the Voyager probe optics and died a couple years ago). Tom shipped the
mirror to QSP, where it arrived on the docking bay, without the shipping
crate. Had several chips along the edge.

What I did was to calculate the percentage of light loss and used that
figure to claim a percentage of the mirror's insured value. The mirror
is equivalent to a 22" mirror and today it's still the best scope in the
area...Dennis

"Phil" <pjsr@bigpond.com > wrote in message
news:bRLji.4310$4A1.3492@news-server.bigpond.net.au...
>I posted some photos in the alt.binaries.picture.astro newsgroup of the
>damaged done to my 17.5 inch mirror during shipping from the supplier.
>Thank god there was insurance on the goods.
>
> Phil
>



 
Date: 08 Jul 2007 01:17:53
From: Phil
Subject: Re: Damaged mirror
The mirror was insured, but the insurance company doesn't want to pay out
too bad for them they are going to have too. A replacement mirror is being
made now so hopefully I will get the insurance sorted out by the time it is
finished. The mirror works well, in fact it is a darn good mirror which
makes this even more heart breaking, made by Terry Ostahowski for discovery.
What doesn't show in the photos is a huge stress fracture. I had a sudden
change in temperature last night and the figure distorted badly for about 20
minutes until it equalised, it was like using a really really badly
collimated telescope for a while, the stars developed comet tails being
allot longer and wider on one side of the field, it was funny to watch, as
the mirror equalised slowly the tails slowly shrunk until they disappeared.

If the weather is good I will give the mirror a star test tonight and I will
photograph the airy disks on star tests tonight and if I get another sudden
temp drop the changing airy disks.

Also my biggest fear is while transporting it to dark sites any jolts may
make the facture worse until .......... the unthinkable. Even though I
brought it in a discovery dob I am halfway through building a new Dob
structure with a Optex 3 inch temp compensating focuser, Optex field
derogator and servo cat drive for astrophotography. This mirror was going
to be the heart of my new astrophotography set up. I need it replaced, hope
the next mirror is as good as this one.

Phil
"Phil" <pjsr@bigpond.com > wrote in message
news:bRLji.4310$4A1.3492@news-server.bigpond.net.au...
>I posted some photos in the alt.binaries.picture.astro newsgroup of the
>damaged done to my 17.5 inch mirror during shipping from the supplier.
>Thank god there was insurance on the goods.
>
> Phil
>




 
Date: 07 Jul 2007 15:11:57
From: thad@thadlabs.com
Subject: Re: Damaged mirror
On Jul 7, 5:40 am, "Phil" <p...@bigpond.com > wrote:
> I posted some photos in the alt.binaries.picture.astro newsgroup of the
> damaged done to my 17.5 inch mirror during shipping from the supplier.
> [...]

This may put you in a better mood (re: McDonald Observatory):

<http://www.astr.ua.edu/keel/telescopes/mcdonald.html >

:-)