William Optics Zenithstar 81 APO

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William Optics Zenithstar 81 APO


The William Optics Zenithstar 81 is a two element designed APO refractor.
Using FPL-53 glass this telescope provides excellent aberration correction.

Features include:

  • Smooth, stable and reliable rack and pinion 2.5″ focuser
  • Built-in Bahtinov mask
  • CNC Handle bar with dovetail slot
  • Soft carry case is included


Z81 Features


Focal Length 559mm
Diameter 81mm
Aperture F6.9
Camera Format APS-C, Full Frame
Focuser 2.5″ Rack and Pinion
Image Circle 44mm
Recommended Flattener FLAT 6A III
TubeLength (Retracted) 460mm
TubeLength (Extended) 560mm
OTA Weight 3.53kg

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