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Old 31-10-2019, 07:36 PM
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Bobbyoutback
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Join Date: Oct 2009
Location: Broken Hill
Posts: 361
Quote:
Originally Posted by ngcles View Post
Hi Bobby,



Yep, before my 31cm f/5.3, I had an AOS 10" -- mine was about f/6.1-ish and full-thickness. The substrate was unusual -- not the normal clear pyrex but it had a distinctly light greenish tint. I later discovered the glass was the Schott equivalent to Pyrex (a Corning T.M product) called Duran 50. Functionally and chemically identical to "real" pyrex apparently -- just looks a tad different.

About 2,700 of my individual observing notes in my log were made with that 10 f/6.1". The mirror was excellent. Then I added about 800 notes with the 12" f/5.3 before the 18" f/4.9 arrived -- with which I added about 3,000 more observing notes. Since the 25" f/5 I've added about 600 new notes in 14 months. Currently a bit over 7,000 individual observing notes -- nearly 6,000 differnt objects observed.

Still haven't tired of visual observing!

Best,

L.
Hello Les ,
I've never heard about that Duran 50 but sounds like the 10" f/6.1 was a great scope ~ 2700 visual notes taken - Wow !

And then the apertures started to go up & up
What a fantastic effort to notch over 7,000 individual & close to 6,000 different objects observed .

Bet you don't need a go to system nor star atlas !

I have a 12" f/5 & have never looked through a big scope
If you get the chance can you describe the visual difference between your 25" & what I can see through my 12 " please ?

Cheers & Beers
Bobby .
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