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Old 09-12-2017, 10:16 AM
bigjoe (JOSEPH)
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Join Date: Nov 2010
Location: sydney
Posts: 1,363
Quote:
Originally Posted by brian nordstrom View Post
You do that , as my C9.25 has never failed to impress on all objects it's an exceptional telescope easily besting a very expensive 130mm triplet APO every time and it mounts as easily as the 130 APO . ( I know this will ruffle a few feathers , but there is no substitute for aperture , as a C14 would easily beat my scope ) .

On that an AVX or HEQ5 would be perfect , I was just lucky to find a sweet CI700 mount 2nd hand here and it don't break a sweat holding the C9.25 .

On the size I have a good friend with the exact same scope but in the C8 format and the size and weight difference is really not that much , a bit longer but at a glance they are more alike than different and on deep sky that extra 1 1/4 inch is very noticable .

Planetary it is also better taking good magnifications on good nights , I regularly hit 400-500x on Mars , Saturn and Jupiter , great stuff when the atmosphere allows .

Last thing , don't worry about columation , its easy and a set of ' Bob;s Knobs ' is $20 well spent . See mine in the photo , they are the cat's whiskers for this .

Hope this helps .

Brian.
Hi Brian..kept these polychromatic strehl figures for C9. Kept these from an article which I no longer have..take it or leave it for what it is...NOT here to prove anything.
235mm (9.25") f/2.5 f/10 Aplanatic SCT with 35% CO:

L 486nm Strehl=0.958
L 546nm Strehl=0.9978
L 656nm Strehl=0.940
As you can see these are high figures.. the c8 for example drops off a lot away from green .
Primary is f2.5 not f2..so a Flatter field and Strehl results..its a long tube scope for its diameter..
Ed Ting says the primary has been finished as parabolic..so a variation to normal.
PS if someone whats an argument.. go ahead I will not respond .
For the record, I recently sold a meade 10 SCT AND 7 SW Mak, M8 etc.
cheers bigjoe.
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