The 10 Best Mirror star diagonals (2023 reviews)

We consider a mirror star diagonal to be a worthy investment in the long run. We are here to help you choose the right one for your needs from all the best available products in market today.

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Our Top Picks:

Celestron Mirror star Diagonal Buy: READ REVIEW

SVBONY Mirror star Diagonal Buy: READ REVIEW

Astromania Mirror star Diagonal Buy: READ REVIEW

Orion Mirror star Diagonal Buy: READ REVIEW

a Alstar Mirror star Diagonal Buy: READ REVIEW

William optics Mirror star Diagonal Buy: READ REVIEW

Oumij Mirror star Diagonal Buy: READ REVIEW

Astromania correct image Buy: READ REVIEW

GRUS Mirror star Diagonal Buy: READ REVIEW

GRUS Mirror star Diagonal Buy: READ REVIEW

Celestron Mirror star Diagonal

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The celestron mirror star diagonal should be able to handle its purpose and duties with ease. This Celestron 2-Inch XLT Diagonal Mirror (with the included 1.25" eyepiece adapter) is a fine, well-made piece of equipment. It serves the function of the visual back AND the star diagonal, and does NOT require any additional parts to attach to Celestron SCTs. It is machined with precision instruments to make sure the optics stay perfectly aligned. It can carry the weight of these big eyepieces.

This item will attach directly to the back of your Celestron SCT *IN PLACE OF* the visual back that comes with the scope. The optical quality is good, but the attachment to the scope is rough, as if there is always grit on the threads. The case is useful while observing to hold lens covers and extra bits, because you can close the lid so they don't blow away.

• High quality diagonal with a beautiful fit and finish
• A beautiful and convenient case for storing a diagonal mirror
• Delivers what they promise

SVBONY Mirror star Diagonal

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We know from years of feedback from readers, customers and amazon sellers, what most people want in a convenient and appropriate diagonal. The svbony mirror star diagonal is exactly that - it's a simple diagonal that hits all the right notes. There are similar SVBONY diagonals with silver side plates that are described as Dielectric. This diagonal is marked " 99 % dielectric coated " which refers to the mirror reflectivity. It fits 1.25 inches telescopes and also fits telescopes with 1.25in focusers. It features more precision and prevents barrels or the surface of eyepieces from marring and scratching. It comes with dielectric coatings to reduce reflected light loss.

The 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. 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. It is good for space viewing, for there is no upside down or right side up in space.

• For more comfortable overhead viewing through refractor and cassegrain type telescopes
• Nicely machined all metal construction except for the mirror
• New and hot release

Astromania Mirror star Diagonal

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The astromania mirror star diagonal gives the top-tier diagonal a run for their money by offering flagship specs at a much more affordable price. 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. The nose piece and eyepiece holder both have the same threading so are interchangeable. It comes with dielectric coatings for the most light transmission possible. It makes the structure more durable.

• Edge to edge clarity with no noticeable distortions or abberations
• Fogs up when the humidity is higher than
• New and hot release

Orion Mirror star Diagonal

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The orion mirror star diagonal is satisfactory and appropriate and fits well with your daily purpose. The 25 inch dielectric twist-tight 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. The 25 inch nosepiece barrel is conveniently threaded to accept like-sized filters so you can easily swap between different telescope eyepieces and other accessories without the hassle of re-attaching the filter each time.

The 25 inch dielectric twist-tight mirror star diagonal is built around a highly reflective mirror with sophisticated, lab-tested dielectric coatings providing 99% reflectivity. It will flip the image depending on the scope set-up. There is NO slop in fitting and the twist tight secures the eyepieces very securely and looks great as well. It is a great addition for easier viewing.

• Image quality is improved over diagonal that came with telescope
• Tight clamping mechanism that securely grasps inserted
• Well made and works even better
• All metal construction with anodized red aluminum twist tight collar

a Alstar Mirror star Diagonal

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This Alstar star diagonal has a 1.25" metal barrel. The clamping screws lock the barrel firmly in place without scoring the nosepiece, as is the case with many cheaper products. It is made with machined metal and a quality mirror. The chrome finish not only looks good, but is also practical, as the star diagonal always remains firmly attached to the focuser. This barrel will keep your star diagonal in condition for virtually forever.

• Protective coating on the mirror to ensure a long life, metal barrel
• Useful for refractor and cassegrain telescopes
• Good brand reputation

William optics Mirror star Diagonal

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We know from years of feedback from readers, customers and amazon sellers, what most people want in a convenient and appropriate diagonal. The william optics mirror star diagonal is exactly that - it's a simple diagonal that hits all the right notes. 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. The bright diagonal is designed with several unique features to provide optimum performance and years of use. 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.

• Very well made item, very nice optics
• Polished to 1/10th wave or better accuracy
• Heavy duty, crystal clear, safely shipped
• High-quality machining out of the best aluminum

Oumij Mirror star Diagonal

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Oumij line of diagonal come in a pretty wide variety of styles, so you can definitely find one that suits your individual preferences and needs. 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. The Wide 45 degree angle makes you view the correct image from the refractor telescope stand and just look down with a comfortable angle. It fits for a 1.25inch telescope eyepiece and focuser.

• Work with refractor and catadioptric telescopes
• Plastic body with optical glass lens, providing clear and sharp image
• One of the new comers and featured product

Astromania correct image

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If you often find yourself scrambling for appropriate and satisfactory diagonal, astromania correct image should be your first option for buying. The diagonal mirror is designed for use with telescopes that have a 1.25 inch diameter optical path. It has a 1.25" metal barrel. The high quality of the mirror makes the image seen clearer and brighter. It throws focus off when switching lenses. It provides a comfortable 90 degree view from your refractor.

The mirror has everything that is possible optimised, it is the link between your eye and the telescope. The image is sharper, cleaner, and brighter. This barrel will keep your star diagonal in condition for virtually forever.

• Gets the job done with smaller budget telescopes
• Protective coating on the mirror to ensure a long life, metal barrel
• Delivers what they promise

GRUS Mirror star Diagonal

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The grus mirror star diagonal is capable of outshining several other diagonal featured in this list in overall features for the price point.

• Good investment for long term
• New and hot release

GRUS Mirror star Diagonal

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Next on the list, we've got yet another diagonal that manages to win our hearts. It's the grus mirror star diagonal and it's widely considered as diagonal that has the most suitable features.

• Lot of satisfied buyers
• Good brand reputation