2" Dielectric Mirror Diagonal, TwistLock
$249.95
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2" Dielectric Mirror Diagonal, TwistLock
$249.95
99% Reflectivity
58 Layer Dielectric Coating
Twist Lock Holder
Self Centering Eyepiece Clamping
Dual Telescope Barrels
Fits Refractor And SCT Focusers
2 Inch Optics
Provides Wider Field View
Machined Aluminum Build
Durable Anodized Mechanical Parts
1.25 Inch Adapter
Includes Stepdown Twist Lock
Starlight Clarity UpgradeMaximized Transmission For Telescope Eyepieces
The Celestron Dielectric Star Diagonal, 2” with Twist-Lock delivers exceptional light transmission with over 99% reflectivity for dramatically brighter visual astronomy. Engineered with 58 layers of dielectric coatings and diffraction-limited BK7 glass, this premium telescope diagonal elevates visual clarity without replacing your entire telescope setup. Ideal for refractors and Schmidt-Cassegrain optics, it offers unmatched versatility and secure optical alignment.
Superior Optical CraftsmanshipEngineered For Peak Astronomical Performance
Upgrade your stargazing experience with the Celestron Dielectric Star Diagonal, 2” with Twist-Lock. Featuring a 90-degree viewing angle for ergonomic comfort during long observing sessions, this high-performance star diagonal utilizes a 58-layer dielectric coating applied to precision BK7 optical glass. The innovative twist-lock mechanism securely clamps eyepieces perfectly on-axis without using traditional thumbscrews that scratch eyepiece barrels. Constructed from durable black anodized machined aluminum with glare-threaded interiors, this 2-inch star diagonal includes interchangeable barrels for standard 2-inch focusers and threaded SCT focusers, plus a 1.25-inch twist-lock stepdown adapter for total eyepiece compatibility.
Technical SpecificationsFull Construction And Dimension Breakdown
Diagonal Size
50.8mm / 2"
Diagonal Type
Mirror
Glass Material
BK7
Coatings
Dielectric, 58 layers
Reflectivity
Over 99%
Optical Quality
Diffraction limited
Eyepiece Holder
2" Twist-Lock
Stepdown Adapter
Included 1.25" Twist-Lock
Compression Ring
Dual rings for 2" holder, single ring for 1.25" adapter
Housing Construction
Machined black anodized aluminum
Barrels Included
2" refractor barrel and SCT adapter barrel
Barrel Interior
Glare threaded and flat black paint
Filter Threads
2" filter threads on barrel and adapter
Product Dimensions
152.4mm x 76.2mm x 101.6mm / 6" x 3" x 4"
Product Weight
19 oz / 538.6 g with stepdown adapter
Key Diagonal HighlightsAdvanced Features For Night Sky Visuals
Dielectric Coatings58 layers providing over 99% light reflectivity
Twist-Lock MechanismCenters and holds eyepieces without scratching barrels
Dual Interchangeable BarrelsIncludes standard 2-inch refractor barrel and SCT threaded adapter
1.25-Inch Stepdown AdapterAllows seamless connection of smaller eyepieces
Anodized Aluminum ConstructionDurable machined black and orange anodized finish
Anti-Reflection InteriorGlare threaded and painted flat black to reduce stray light
Integrated Barrel StopPrevents 2-inch accessories from striking the internal mirror
Frequently Asked QuestionsEverything you need to know
What telescopes are compatible with the Celestron Dielectric Star Diagonal, 2” with Twist-Lock?
The Celestron Dielectric Star Diagonal, 2” with Twist-Lock includes two interchangeable barrels, allowing it to connect directly to refractors with standard 2-inch focusers as well as Schmidt-Cassegrain (SCT) telescopes using threaded focuser connections.
How does the twist-lock mechanism on the Celestron Dielectric Star Diagonal, 2” with Twist-Lock work?
The twist-lock system tightens an internal ring evenly around the eyepiece barrel when rotated, centering the eyepiece accurately on the optical axis while preventing thumbscrews from scratching or denting your eyepiece barrels.
Can I use 1.25-inch eyepieces with the Celestron Dielectric Star Diagonal, 2” with Twist-Lock?
Yes, the Celestron Dielectric Star Diagonal, 2” with Twist-Lock comes included with a 2-inch to 1.25-inch stepdown adapter featuring its own twist-lock holder.
What are the benefits of the 58-layer dielectric coating on the Celestron Dielectric Star Diagonal, 2” with Twist-Lock?
The 58 layers of dielectric coating provide over 99% reflectivity across the visual spectrum, ensuring maximum light transmission to the eyepiece for brighter and sharper astronomical views.