Agena 1.25" 90-deg Mirror Star Diagonal for Refractors
Stock count is accurate & shown in real time.
- This item is out of stock.
- Sign up for back-in-stock alerts to be notified when this item becomes available (account login required).
- This item is out of stock.
- Sign up for back-in-stock alerts to be notified when this item becomes available (account login required).
Contiguous US / Lower 48:
Free shipping applies to orders over $50 using our chosen carrier/method. Faster paid options are available at checkout.
Alaska, Hawaii & US Territories:
Free shipping applies to many—but not all—products. Enter your ZIP code in cart or upon checkout to confirm options and costs.
International:
International orders do not qualify for free shipping. Shipping, duties, brokerage, tariffs, and taxes are the customer’s responsibility. Some items may be restricted due to export, size, or manufacturer limitations.
- Economical 1.25” 90-deg star diagonal for refractor or catadioptric scopes
- Precision grade, aluminized λ/4-wave mirror with MgF2 coating at 92% or better reflectivity
- Threaded for standard 1.25” filters
Agena's 90-deg mirror diagonal is a very good, economical replacement for the generic diagonal that probably came with your otherwise fine scope. This diagonal features a precision grade mirror made of K9 glass (equivalent to BK7) with an RMA surface accuracy of λ/4 (measured at 546.1nm).
Features Al + MgF₂ coatings with minimum 92% reflectivity across the visible spectrum . A brass compression ring in the 1.25" holder will prevent your eyepieces from getting marred by the setscrew.
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, and 1 dust plug and 1 end cap are included.
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.
Specifications:
- Weight: 2.9 oz / 82 g
- Optical path length: 68 mm
- Insertion depth: 28 mm
- Has safety stop inside 1.25" holder: Yes
Other Information
- Country of Manufacture: China
Agena's 90-deg mirror diagonal is a very good, economical replacement for the generic diagonal that probably came with your otherwise fine scope. This diagonal features a precision grade mirror made of K9 glass (equivalent to BK7) with an RMA surface accuracy of λ/4 (measured at 546.1nm).
Features Al + MgF₂ coatings with minimum 92% reflectivity across the visible spectrum . A brass compression ring in the 1.25" holder will prevent your eyepieces from getting marred by the setscrew.
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, and 1 dust plug and 1 end cap are included.
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.
Specifications:
- Weight: 2.9 oz / 82 g
- Optical path length: 68 mm
- Insertion depth: 28 mm
- Has safety stop inside 1.25" holder: Yes
- Economical 1.25” 90-deg star diagonal for refractor or catadioptric scopes
- Precision grade, aluminized λ/4-wave mirror with MgF2 coating at 92% or better reflectivity
- Threaded for standard 1.25” filters
Agena's 90-deg mirror diagonal is a very good, economical replacement for the generic diagonal that probably came with your otherwise fine scope. This diagonal features a precision grade mirror made of K9 glass (equivalent to BK7) with an RMA surface accuracy of λ/4 (measured at 546.1nm).
Features Al + MgF₂ coatings with minimum 92% reflectivity across the visible spectrum . A brass compression ring in the 1.25" holder will prevent your eyepieces from getting marred by the setscrew.
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, and 1 dust plug and 1 end cap are included.
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.
Specifications:
- Weight: 2.9 oz / 82 g
- Optical path length: 68 mm
- Insertion depth: 28 mm
- Has safety stop inside 1.25" holder: Yes
Other Information
- Country of Manufacture: China
Agena 1.25" 90-deg Mirror Star Diagonal for Refractors