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Used William Optics RedCat 51 f/4.9 APO Refractor Telescope in excellent condition.

Includes a red William Optics Cat Series Saddle Handle Bar, William Optics 1.25" 90 degree Erecting Prism, and 48mm Sony E-mount. 

This Petzval refractor boasts 4 elements of Ohara FPL53 glass providing you with pinpoint stars, perfect color correction, and zero chromatic aberrations in your astrophotos and through your eyepiece. Its miniature size provides beginner and advanced astrophotographers with an incredibly portable telescope for both wildlife photography and astrophotography.

The RedCat telescope mounts on a photographic tripod or an equatorial mount with the reversible base that has Arco-Swiss mounting on one side and a standard Vixen dovetail on the other.

​APO performance means you’ll have virtually zero chromatic aberration. The Petzval design, which consists of four elements in three groups, also known as a Quad, produces a full frame flat field, with an image circle of 44 mm (full frame).

Included within this ingenious design are a full 360 degree rotator, a tilt adjustment plate, and integrated m48 threads for any 2” filter of your choice. A built-in bahtinov mask to achieve precise focus is also included.  

Focal length: 250mm
Focal ratio: f/4.9
Aperture: 2" (51 mm)
Focuser Style: Helical
OTA Length - Retracted: 8.3" (210 mm)
OTA Lenght - Extended: 12" (305mm)
OTA Weight: 3.9 lb
Image Circle Size: 44 mm (full frame)

Instructions