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GSO 2" 90-deg 99% Quartz Dielectric Mirror Diagonal for Refractor Telescope

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  • Premium 2" diagonal with durable dielectric coatings for 99% reflectivity for bright images and long lifetime
  • 1/12-wave quartz mirror offers good thermal stability and minimal focus shift during long observing or imaging sessions
  • All-metal body with chrome barrel threaded for standard 2" filters
  • Comes with 2"-1.25" eyepiece adapter for maximum flexibility
  • Includes foam-fitted storage box and end caps

If you want a high-end mirror diagonal for your refractor telescope, this GSO 2" Quartz Dielectric Diagonal Mirror is an excellent choice. GSO's 2" refractor diagonal features dielectric coatings with 99% reflectivity across the visible spectrum and a 1/12 wave quartz mirror. The all metal diagonal body is CNC machined. The combined result is a superb diagonal offering excellent mechanical and optical quality at a great price. Dielectric coatings are more durable than regular or enhanced aluminum coatings, so you will enjoy years of excellent performance from this product. Diagonals with comparable quality and specifications often sell for $200 or more in today's astronomy market.

High quality diagonal mirrors are usually made of BK7 glass. Quartz glass goes a notch higher - it offers greater thermal stability, resulting in minimal thermal expansion and contraction as compared to other glass types. The result is a minimal, if any, shift in focus due to temperature changes over long observation sessions, making this quartz diagonal ideal for photographic and imaging applications.

The 2" chrome barrel of this diagonal on the telescope end is threaded to accept standard 2" filters. A 1.25"-2" adapter is included so you can use this diagonal with 1.25" or 2" eyepieces. The 1.25" and 2" holders both feature a brass compression ring, so your eyepiece barrels will not be scratched by the set screw. The 1.25"-2" adapter is also threaded to accept 2" filters. The clear aperture is 46.6mm. The diagonal comes in a very nice foam-fitted storage box and includes 2 end caps. Weight = 1lb-3oz. (with 1.25" adapter); 1lb. (without 1.25" adapter). Made in Taiwan.


Note: Occasionally, the product you receive might have a slightly different cosmetic appearance or labeling than what is shown. This can often change from batch to batch according to the whims of the manufacturer. However, you will always receive a brand new, original product as described above.

Description copyright: Agena AstroProducts - Reproduction without permission prohibited.

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Filed under: Eyepieces & Accessories