GSO 1.25" 90-deg Mirror Star Diagonal for Refractors # GSST

Our #: ODIA-GS-GSST
Mfg #: GSST
Our Price: $30.00
Free shipping for this item in the US
More Info

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Out of Stock
Availability: Unknown at this time. Not until mid-late 2024.

Quick Overview

  • Economical 1.25” 90-deg star diagonal for refractor or catadioptric scopes
  • Aluminized 1/10-wave mirror with SiO2 coating at 92% reflectivity
  • Threaded for standard 1.25” filters

Product Details

New version: Now with brass compression ring!

GSO's 90-deg mirror diagonal is a very good, economical replacement for the generic diagonal that probably came with your otherwise fine scope. Features Al+SiO2 coatings with 92% reflectivity across the visible spectrum and a 1/10 wave mirror.

The clear aperture is 27.9mm. The main mirror housing is made of precision molded ABS plastic and the two end barrels are precision machined from aluminum. The 1.25" nosepiece is threaded to accept standard 1.25" astronomy filters. Weight: 4.4oz; 2 end caps included. Made in Taiwan.

GSO has not specified the optical path length of this diagonal, but our measurements indicate that is is 76mm.

Please Note: This diagonal can only be used with refractor telescopes and some catadioptric telescopes like Schmidt-Cassegrain, Maksutov-Cassegrain, etc. It not meant for use with Newtonian / Dobsonian reflector telescopes or other variants of Newtonian telescopes.

Other Information

  • Country of Manufacture: Taiwan