Astro-Tech 8-inch f/8 Ritchey-Chretien Review

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PROS / Offers a great combination of quality optics, portability and ideal design elements.

CONS / We appreciate Astro-Tech's 2-year warranty but would like to see additional customer support options.

VERDICT / The designers thought of everything an astrophotographer would want in an entry level instrument.

It is not easy to design ideal astrophotography beginner telescopes. Even if you get the optics as perfect as they can be within the entry level price range there are many other factors that impact the success of an astrophotograph, including the quality of the mount and camera, method of guiding and the software used to process the image. Even if all of those “stars” align, there are still other elements to contend with, especially at the beginner level. Any astrophotography enthusiast will say, however, that the images you can create will be worth the trouble. As we weighed the assortment of astrographs at the entry level, we tried to narrow the field based on the instrument that is most likely to facilitate great images as you continue your journey with astronomy and begin to experience astrophotography. The 8-inch Ritchey-Chretien from Astro-Tech fits the bill with a great combination of quality optics, portability and ideal design elements and earns our TopTenREVIEWS Gold Award.

Standout Features

  • Ritchey-Chretien optical design
  • High strength/low thermal expansion carbon fiber body
  • Low expansion quartz mirrors
  • Double dovetail mounting rails


Buy this product from Astro-Tech only if you like the idea of having at your disposal the same basic optical design as many of the best telescopes used in research. The Hubble Space Telescope, Keck Interferometer, Gran Telescopio Canarias and other tools being used to explore the Universe and beyond use the same basic design – Ritchey-Chretien. Early in the 20th century American George Willis Ritchey and Frenchman Henri Chretien built the first Ritchey-Chretien telescope (RCT), which is a type of Cassegrain that is good at eliminating coma (an aberration that can make stars and comets look blurry).

Ritchey-Chretien is considered by many to be the best for taking pictures of celestial objects, but optical design is just one of the ways this telescope sets itself apart. Among the most important distinctions are the materials used to build it. Forget the optical glass used in other instruments. The primary and secondary mirrors in Astro-Tech’s Ritchey-Chretien are made of low thermal expansion quartz. The mirror coating is also exceptional. Instead of the usual aluminum there is 99 percent reflective dielectric mirror coatings. The coatings are designed to be non-tarnishing and offer exceptional reflectivity.

The optical tube has ten contrast-enhancing glare-stop baffles. There are multiple glare-stop micro-baffles in the secondary mirror light shield and five baffles in the primary mirror baffle tube. These features offer the dark backgrounds that are ideal for astrophotography. While some RCT designs incorporate motors to focus the secondary mirror, the 8-inch Ritchey-Chretien from Astro-Tech features a fixed secondary mirror. Focusing takes place externally with a dual-speed focuser that can make tiny adjustments. The designers really thought of everything an astrophotographer would want in an entry-level instrument. Details like the two mounting rails are a great idea. Even at the earliest stages of this hobby, participants will most likely want full control over what mount, tripods, guiding tools and other accessories they use. The slightest changes in those areas can make a big difference to your photograph.

This Astro-Tech product includes rails that give you the option of pairing your scope with the Vixen or Losmandy-style mounts. You can also employ those rails to mount a wide range of accessories like a piggyback camera adapter. You will also have a choice in the type of finderscope you select. The mounting shoe will work with a wide range of instruments so you can install whichever you prefer. You can mount Vixen-style finderscope brackets or red dot finders. The tube itself offers quality materials that will help you create your dream space photos. The tube may seem irrelevant, just a shell to contain the important components, but it is one of the important components in this case. It is made of lightweight carbon fiber-reinforced composite material. This stuff is extra strong and lightweight, and it can reduce focus changes due to temperature.

The scope comes with two threaded extension tubes to install singly or in combination between the AT8RC rear cell and the focuser, providing a solid extension that changes the distance between the focuser and rear cell. This will help you accommodate DSLR and CCD cameras. The designers added creature comforts like a dust cap and storage case. You will not likely be using either any time soon because you will be having too much fun using this telescope to put it away.

Viewing Experience

Expect to see a wide and coma-free photographic field through the AT8RC and expect to be impressed by its light gathering capabilities compared to other astrophotography beginner telescopes. The included, removable Crayford focuser will help you get exactly the picture you want by facilitating very fine adjustments to the focus. It’s easy to move the focuser itself too. It can be rotated by loosening the collar and tightening it back up when it is in the right place. A heavy equipment train may cause the focuser drawtube to tilt a bit when fully extended, which can impact the focus. You can adjust the position of the focuser with two included extension tubes though.


The AT8RC is not the lightest of our astrophotography beginner telescopes lineup. It offers so much value for the price, though, that we are willing to give it a lot of credit for all the things it has. The scope’s 16 pounds should not be considered prohibitive anyway. That is still well under the weight limit most people would set for what they are willing to pack into the SUV for a weekend astrophotography session. This telescope is about 18 inches long. It was not the shortest we reviewed but still very portable. We think users will find the transport of the AT8RC well worth it when they see the photos they can create with it.



The help and support seems fairly limited. There is a contact e-mail address and a mailing address on Astro-Tech’s website but no phone number to be found. That’s pretty frustrating, especially for someone who is new to astrophotography. There is not likely to be an astrophotography emergency but this telescope represents a pretty big investment. Patrons will want some support from the manufacturer. This telescope is so great we think it is very likely worth a little bit of a slow response on your questions. We’re talking about a true 8-inch aperture on a Ritchey-Chretien design that is relatively affordable. Astro-Tech does offer a 2-year warranty, which is perhaps the best show of confidence any manufacturer can offer for their product. If you find any flaws in materials or workmanship, you can expect Astro-Tech to take care of it.


The 8-inch Ritchey-Chretien from Astro-Tech is the perfect answer for an astronomer that wants to explore the field of astrophotography but assumed all of the sophisticated scopes were permanently out of their price range. At roughly $1,400, it is certainly not free but you are destined to get back every penny in the form of sheer enjoyment. It is a great way to enter astrophotography with a scope that is not so sophisticated as to become cost-prohibitive but not so simple that it will quash your interest either. It’s just right for anyone shopping for astrophotography beginner telescopes.