Astro-Tech 6" f/9 Ritchey-Chrétien Astrograph


Hubble at home

This is probably the most economically viable Ritchey-Chrétien telescope money can buy. It can be found for around $350 at most places. I bought this one used for even less. The Ritchey-Chrétien design is probably most famous for being the same optical design that's in the Hubble Telescope. This is probably the largest scope I can feasibly put on my mount for weight reasons. The AVX has a 30lb max payload capacity, and the AT6RC is around 13lbs with no other gear. So, I'm probably pushing 18-20lbs of astronomical gear with this scope. Due to the long focal length (~915mm with the AP CCDT67 reducer), getting the polar alignment dialed in is crucial. But once set, I'm able to get some half way decent images out of it. I'm currently imaging with it at F/6. This allows me to get as close as possible to objects on this mount without taxing it too much. At the native focal length of 1370mm and F9, I struggled to regularly get great results.

These images show all the gear set up and ready for a night of imaging. Pictured here is the AVX mount, AT6RC, Orion 60mm Guide scope, ZWO ASI1600MM-Cool camera for primary imaging, ZWO ASI224MC camera for guiding, with a CCDT67 Astro-Physics Telecompressor, the ZWO 8 slot electronic filter wheel with Astrodon LRGB and Narrowband filters, an Astrozap dew heater on the guide scope, Astrozap dew shield (not shown), and a 2.5” Moonlite CSL focuser with stepper motor.

The Pelican Nebula - Imaged with this telescope.

The Pelican Nebula - Imaged with this telescope.