Mak-Newts

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

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.

On Monday, July 18, 2016 at 2:12:02 AM UTC-7, 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.

What i read, reason for the larger CO is for photography. Before with the 19% CO was more difficult to do photo, unless the camera/imager had a small CCD.

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.

On Monday, July 18, 2016 at 7:30:52 AM UTC-7, Chris L Peterson wrote:
On Mon, 18 Jul 2016 02:11:58 -0700 (PDT),

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.

Right! It's in the name - Astrograph-! So, it's primary purpose is photography, not visual observation!

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?

On Monday, July 18, 2016 at 3:46:28 AM UTC-6, StarDust wrote:

What i read, reason for the larger CO is for photography. Before with the 19%
CO was more difficult to do photo, unless the camera/imager had a small CCD.

Interesting. Usually, a larger central obstruction is found in photographic
telescopes to better correct aberrations, and because contrast is not as
important for photography as for visual observing.

It certainly can be true that a small central obstruction could lead to
vignetting, particularly in prime focus photography, but this is the first time
I've heard of it being a consideration.

John Savard

On Mon, 18 Jul 2016 09:10:01 -0700 (PDT), RichA
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.

On Monday, 18 July 2016 18:22:08 UTC-4, Chris L Peterson wrote:
On Mon, 18 Jul 2016 09:10:01 -0700 (PDT), RichA
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.

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.