The 9 Best Dielectric Mirror diagonals (2023 reviews)

Next on the list, we've got yet another diagonal that manages to win our hearts. It's the svbony dielectric mirror diagonal and it's widely considered as diagonal that has the most suitable features. There are similar SVBONY diagonals with silver side plates that are described as Dielectric. It features more precision and prevent barrels or the surface of eyepieces from marring and scratching. It comes with dielectric coatings to reduce reflected light loss. It features more precision and prevents barrels or the surface of eyepieces from marring and scratching.

The degree mirror comes with the caps for both ends, a nice solid box with foam to help protect the lens and a lens cleaning cloth. It is easy to use and helps to get aligned. It is good for space viewing, because there is no upside down or right side up in space. Those attractive, shiny, red anodized, aluminum side plates are also shiny on the inside of the diagonal, and that can result in internal reflections that reduce contrast.

Why We Like This:

Provide an over 99% reflective surface
Nicely machined all metal construction except for the mirror
Super flat mirror with dielectric coatings to reduce reflected light loss

Serounder Dielectric Mirror Diagonal

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It is a very good diagonal with a clear image. It is constructed with aluminum alloy housing and stainless steel cover plate, available for long lifespan. The image is inverted (upside down) as these diagonals usually do and it is clear, in focus. It is used for 1.25 inch focus seat and 1.25inch eyepiece.

Why We Like This:

Good brand reputation
One of the new comers and featured product

Astromania Dielectric Mirror Diagonal

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Best part: astromania dielectric mirror diagonal costs comparatively low and it is available to ship in 24 hours. Dielectric coatings are more durable than regular or enhanced aluminum coatings, so you will enjoy years of excellent performance from this product. It fits all rear cells of Schmidt-cassegrain telescopes equipped with a big, 2" focuser and can use with refractor telescopes with sct adapter asin. It features a brass clamping ring which does not mar, and provides a more secure connection. It makes observations quite comfortable when the telescope is at or near the zenith.

The 2" diagonal features dielectric coatings with 93% reflectivity across the visible spectrum and a 1/10 wave mirror for bright and true images. It makes the structure more durable. The nose piece and eyepiece holder both have the same threading so are interchangeable. It allows you to take advantage of the wider field of view provided by two inch eyepieces.

Why We Like This:

Edge to edge clarity with no noticeable distortions or abberations
Fogs up when the humidity is higher than
Good brand reputation

Orion Dielectric Mirror Diagonal

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Not everyone likes to purchase diagonal for their regular usage, but the orion dielectric mirror diagonal would be an anomoly. The 25 inch twist-tight dielectric mirror star diagonal gives the typical thumbscrew-equipped telescope diagonal a new twist. It features machine-threaded internal baffles to ensure optimal contrast and also eliminate pesky internal reflections and glare. This diagonal will improve the view in your refractor telescope. It will flip the image depending on the scope set-up.

It comes with such high reflectivity, this diagonal will help you obtain the brightest views possible through a refractor or cassegrain telescope. There is NO slop in fitting and the twist tight secures the eyepieces very securely and looks great as well. This is a must have, and it makes exchanging eyepieces 100% easier.

Why We Like This:

All metal construction with anodized red aluminum twist tight collar
Well made and works even better
Image quality is improved over diagonal that came with telescope

William optics star Diagonal

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We would, of course, be remiss if we didn't mention william optics star diagonal for daily purpose. The 2 "mirror-type star diagonal has a Dura-Bright 12mm thick mirror, 1/10 or better wave surface accuracy, and dielectric mirror coatings for 99% reflectivity which provides higher contrast and resolution during critical planetary, lunar and binary star observations. It features a 2" nosepiece for insertion into refractor telescopes and other 2" focuser barrels.

The Dura-Bright features 100% real carbon fiber side plates that add that touch of class your scope deserves. It provides higher contrast and resolution during critical planetary, lunar and binary star observations. It allows 99% reflectivity additionally it is easy to turn even with gloves on. It is a big improvement over a basic meade or celestron.

Why We Like This:

Big, knurled thumbscrews are easy to turn even with gloves on
Meticulous craftsmanship 2" to 1.25" eyepiece adapter included
Very well made item, very nice optics
Internal anti-reflection baffling for highest contrast

Oumij Dielectric Mirror Diagonal

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We would, of course, be remiss if we didn't mention oumij dielectric mirror diagonal for regular usage. This diagonal can correct upside down and left-right reversed image easily, which allows you to view things during daytime in the correct position. It comes with dust cover to keep your lens clear, easy to install and use. It fits for a 1.25inch telescope eyepiece and focuser. The Wide 45 degree angle makes you view the correct image from the refractor telescope stand and just look down with a comfortable angle.

Why We Like This:

Plastic body with optical glass lens, providing clear and sharp image
Work with refractor and catadioptric telescopes
New and hot release

William optics Dielectric Mirror Diagonal

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Compared with other diagonal in this category, the william optics dielectric mirror diagonal has a convenient design.

Why We Like This:

Well made and ooozzing with quality
Very nicely machined, feels very nice and mounts cleanly
Beautifully constructed and feels like very high quality

Astrostreet Dielectric Mirror Diagonal

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The astrostreet dielectric mirror diagonal should be able to handle its purpose and duties with ease. The body is made of CNC machined aluminum with a beautiful finish and excellent rigidity.

Why We Like This:

Lot of satisfied buyers
Good investment for long term

Pomya Dielectric Mirror Diagonal

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We would, of course, be remiss if we didn't mention pomya dielectric mirror diagonal for regular usage. It is constructed with aluminum alloy housing and stainless steel cover plate, available for long lifespan.

Why We Like This:

Good brand reputation
New and hot release