OPinions on the following astrophotography scopes

[Carl]

Just been checking the latest offerings for Astro scopes under $1000

Bintel BT250 f/4 Imaging OTA



Orion 10" f/3.9 Newtonian Astrograph Reflector Telescope

Anyone seen any reviews of either?
Both claim to be excellent for astro photography

Cheers
Carl

[A23649]

i have the 8" little brother of the orion and i an vouch for that as an excellent scope

[gregbradley]

I have no specific knowledge of those scopes but general principles.

Fast Newtonian scopes are tricky to collimate, require a light imaging paylod otherwise you will most likely get plagued with twists and flexes that may be hard to track down.

They will als require a corrector otherwise the coma is severe even with a smaller camera like a DSLR. The Baader MPCC is a common corrector used with good results.

I used a cheap Antares laser collimator to collimate a Vixen R200SS 8 inch F4 Newt I had once. That solved the tricky collimation.

The pluses of Newts are they are very sharp for their price as the mirrors are the easiest of all designs to manufacture accurately.

They tend to be very widefield and very sharp. A 10 inch Newt has a lot of potential. I'd say though you will need to upgrade the focuser to a Moonlite or a Feathertouch and get the MPCC and attach your camera with a T-thread adapter rather than an eyepiece holder plus get a cheap laser collimator and it would be a nice machine.

As a general rule in optics fast F ratios are harder to manufacture and keep stable. They generally come at a high price.

Greg.

[Moon]

Carl
What camera and mount are you planning to use?
James

[Carl]

Hi James
I would plan to mount this on a Skywatcher EQ6 pro mount.
The only other weight would be a modified 9x50 finderscope/guidescope, plus my Canon 500d.
The only other payloads would be the mounting rings and a solid universal losmandy style plate.
The whole rig sits in an observatory on a very solid 180mm pier that is sunk 4ft into a hole full of concrete.
My question is will i be over taxing the mount for exposures no longer than 3 minutes?

Cheers Carl

[Moon]

Carl
Why don't you get the 8 inch f/4 instead? The EQ6 will handle it better. You will need a coma corrector as well.
The other option to consider is an 8 inch GSO RC.
James