From: John St†hle 
CC: atm{at}shore.net
Reply-To: John St†hle 



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I have been reading through a lot of postings about 0,001% optimizations
and couldn't help wondering, why?

For each photon reflected from a given area on your primary mirror, lots of
photons are reflected from the same area of your 2ndary. Sample numbers for
d¡fferent obstructions (2nd d/prim D): 30% 10:1
25% 16:1
20% 25:1
15% 44:1

Perhaps it is time to give the quality of your 2ndary mirror a thought.

Everything you gain from perfect primary, perfect cell, ultra thin and
curved spiders, are lost if your 2ndary isn't 10-20-40 times as perfect as
the primary.

. John
--

John St†hle . 12§ 28' 05" E . 55§ 45' 14.6" N . Bagsv‘rd .
Danmark . Skandinavien . Europa

Insured by the Russian mafia: You hit me, they hit you.


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I have been reading through a
lot of postings
about 0,001% optimizations and couldn't help wondering, why?

For each photon reflected from a given area on your primary mirror, lots of
photons are reflected from the same area of your 2ndary. Sample
numbers for dífferent obstructions (2nd d/prim D): 30%
10:1
25% 16:1
20% 25:1
15% 44:1

Perhaps it is time to give the quality of your 2ndary mirror a thought.

Everything you gain from perfect primary, perfect cell, ultra thin and
curved spiders, are lost if your 2ndary isn't 10-20-40 times as perfect as
the primary.

. John
-- 










   
  John
Ståhle  John
Ståhle 
4
2 
2002-11-07T11:05:00Z
  2002-11-07T11:08:00Z
1 
23
135 
netman
1 
1
165
9.2720



 
   



John Ståhle . 12º
28’ 05” E .
55º 45’ 14.6” N . Bagsværd . Danmark
. Skandinavien . Europa
 
 Insured by the Russian mafia: You hit me, they hit you.
 




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