Thread: Mak-Newts
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Old July 19th 16, 06:47 AM posted to sci.astro.amateur
StarDust
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Default Mak-Newts

On Monday, July 18, 2016 at 8:27:38 PM UTC-7, RichA wrote:
On Monday, 18 July 2016 18:22:08 UTC-4, Chris L Peterson wrote:
On Mon, 18 Jul 2016 09:10:01 -0700 (PDT),
wrote:

On Monday, 18 July 2016 10:30:52 UTC-4, Chris L Peterson wrote:
On Mon, 18 Jul 2016 02:11:58 -0700 (PDT), RichA
wrote:

On Monday, 18 July 2016 04:07:07 UTC-4, StarDust wrote:
Anyone had a chance to own/use this 8" Mak-Newt from Orion?
What are the pros/cons of the scope?
It has the same CO-33% than my C-11!
http://www.telescope.com/Gift-Center...767/p/9978.uts

Really defeats the purpose of a Mak-Newt which had as a selling point a smaller secondary by percentage than a Mak-Cass or SCT. There is ZERO reason to buy it over an Mak-Cass or SCT.

Not sure about that. First of all, this is a photographic instrument,
so the size of the obstruction is largely irrelevant. Depending upon
the design details, a Mak-Newt has a larger flat field than a
Mak-Cass, and both of the Mak designs have less off-axis aberration
than an SCT.

Who uses an SCT without corrected optics and at f/10, except for planets where neither issue matters?


Well, yeah. So why do you suggest an SCT over a f/5.3 scope optimized
for large area sensors? Even corrected most SCTs show significant
aberration when using a full frame sensor.


Any examples around? I'd like to see it as I've been considering one of the corrected ones.


What's a corrected SCT? Those f/6 - f/3 focus reducers?
My first SCT, long time ago, was a Meade LX-5 8" f/6, not f/10, it had a huge CO some 40% or more. I think, Meade made it for photography use. Back than 35 mm film was the game.