Used TPO 2" Mirror Diagonal with SCT Thread - Sold

  • Sale
  • $69.00
  • Regular price $123.95
  • ITEM #



  • This is a used item in very good condition
  • The TPO Deluxe Mirror Diagonal is manufactured with 99% reflectivity and dielectric coatings.
  • The BK7 mirror os polished to minimum 10th wave.
  • The TPO Deluxe Mirror Diagonal attaches to rear cell thread of Schmidt-Cassegrain/Maksutov-Cassegrain telescopes.
  • Fully CNC machined housing and includes 1.25 inch adapter.
  • Brass compression rings on both the TPO Deluxe Mirror Diagonal and adapter assure gentle treatment of your eyepieces.

Used TPO 2" Mirror Diagonal with SCT Thread - Sold

The TPO 2 inch dielectric mirror diagonal features 99% reflectivity, dielectric coatings to maximize light output of your telescope system. Our custom made diagonal uses a BK7 mirror polished to 10th wave accuracy or better for best possible image quality.

The TPO 2 inch dielectric diagonal also features a CNC machined housing. This housing is designed to retain the optimal collimation of the mirror and assure the best optical performance. The CNC machined aluminum housing will provide outstanding results for years of use.

This diagonal also includes brass compression rings on both diagonal and the included 2 inch to 1.25 inch adapter, assuring gentle treatment of your eyepieces. Some other brands use set screw locking mechanisms that can mar the barrel surface of your favorite eyepieces. Avoid scratches and gouges by using the OPT dielectric series diagonals.

TPO dielectric diagonals provide outstanding performance with low prices to provide amateur astronomers with excellent value! TPO backs this diagonal with a full 2 year warranty against manufacturer defects, which may be expanded into a lifetime warranty by purchasing a warranty extension.

This diagonal attaches to the rear cell of SCT's. It is not meant for SC telescopes that have an electric focuser attached to the rear cell. In these instances, we recommend the TPO 2 inch Mirror Diagonal.


Additional Information

Accessory TypeDiagonals
BarrelThread On SCT
Construction MaterialAluminum
Mirror CoatingsDielectric
Warranty90 Day
  • 2" SCT dielectric diagonal
  • 2" to 1.25" adapter
  • Caps

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Questions & Answers

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  • how much does this diagonal weigh?

    I put it on the scale here at OPT, and the diagonal weighs 1.3 lbs (0.6 kg).

  • how much does this diagonal weigh?

    I weighed mine on scales which I have cross-checked with the Post Office for accuracy. Complete with 2" to 1.25" adapter and both caps: 19.5 oz (552 g) Without the caps, still with adapter: 19.2 oz (543 g) In 2" mode (no adapter, no caps): 16.4 oz (46

  • What is the difference between this and the Quartz version?

    The quartz version of this diagonal tends to be more thermally stable which means that the mirror cools down faster which will mean in focus images sooner than a standard diagonal. Plus, quartz is more chemically stable which means that the mirror is a li

  • Hello, will this diagonal compatible with the rear cell threads on a Celestron 800 Edge HD OTA?

    Yes, the thread on this diagonal will directly attach to the rear cell of the EdgeHD 800.

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