Name: Celestron Dielectric Star Diagonal, 1.25" with Twist-Lock
Brand: Celestron
SKU: CNDISD
Price: 144.95 USD
Availability: InStock
Rating: 4.8 (18 reviews)

Celestron Dielectric Star Diagonal, 1.25" with Twist-Lock

Celestron Dielectric Star Diagonal

Celestron

In Stock

Adorama Protect 1-Year Protection Plan

Adorama Protect 2-Year Protection Plan

Adorama Protect 3-Year Protection Plan

Adorama Protect powered by Extend is available for purchases to customers in the United States only. Not available for international or U.S. territories purchases. Adorama Protect plans are available for ABS clients.

<a class="percent-off-everyday-promo popup promo-financing trackEvent" data-href="/api/getContent?ContentName=CAFinancingGenericPopup&amp;Output=Desktop" data-popup-class="popupFinancing popup800" rel="nofollow" data-track-data="financing apply,ways to save every day savings,pdp" 
		data-callback-context="adrma" data-callback-arguments="{&quot;financeMonth&quot;:&quot;{1}&quot;,&quot;financePrice&quot;:&quot;{0}&quot;,&quot;TotalPrice&quot;:&quot;{2}&quot;}" data-callback="renderFinancingPromoPopup"><img alt="edge-creditcard" src="/col/assets/edge-creditcard.png">
            <span class="month-term-promo"><h3>Save 5% Every Day<sup>†</sup></h3><p>with the Adorama Edge Credit Card.<span class="promoFinancing">Learn More</span></p></span></a>  

Adorama

Optics & Binoculars

Telescopes & Astronomy

Telescope Accessories

Celestron Telescope Accessories

Celestron Dielectric Star Diagonal 

Enhance your telescope with the Celestron Dielectric Star Diagonal. Features over 99% reflectivity & twist-lock. Shop now for optimal viewing!

From the renowned brand Celestron, comes the innovative Dielectric Star Diagonal, 1.25" with Twist-Lock, a high-quality and reliable accessory for your astrophotography needs. This durable and sturdy star diagonal is designed to maximize light transmission without compromising optical quality, enhancing your viewing experience with brighter, sharper images.This premium star diagonal is an ideal upgrade for your existing telescope setup, reflecting the telescope's light path at a comfortable 90&#189; angle. The glass is meticulously layered with 58 dielectric coatings, creating an over 99% reflective surface that delivers the maximum amount of light to the eyepiece, ensuring optimal clarity and brightness.The Dielectric Star Diagonal features a unique twist-lock mechanism, designed to securely hold any 1.25" eyepieces while maintaining perfect opto-mechanical alignment between the telescope and eyepiece. This innovative twist-lock design eliminates the risk of scratching or engraving the barrel of your eyepieces, a common issue with traditional thumb screws.In addition, the twist-lock mechanism includes an integrated 1.25" barrel stop, providing added protection against potential damage to the mirror from 1.25" accessories with long barrels. The diagonal's mechanical parts are crafted from machined black anodized aluminum, with the exception of the twist-lock rings, which are orange anodized for easy visibility.The interior of the barrel is threaded and painted flat black to prevent glare, ensuring a seamless and uninterrupted viewing experience. With its advanced features and high-end finishes, the Celestron Dielectric Star Diagonal, 1.25" with Twist-Lock, stands out as one of the highest quality 1.25" star diagonals on the market.Compared to standard star diagonals, this dielectric star diagonal excels in both reflectivity and optical quality. With an over 99% reflective mirror and diffraction-limited optical quality, it guarantees that virtually all the light collected by the telescope reaches the eyepiece without affecting optical performance. Upgrade your telescope with the Celestron Dielectric Star Diagonal for a superior viewing experience.

Fantastic improvement in my telescope. Crystal Clear Viewing. And a fantastic price, thank you.

Unbelievable change

A really high quality star diagonal.image quality is clear n crisp which is always the case with celestron products.  And the twist lock feature is a game changer. No more tiny little thumb screw gouging my eye pieces. The twist ring holds firmly n evenly. The orange ring not only looks sharp but stands out allowing u to change eye pieces in the dark more easily.

This small upgrade makes using my scope a little bit better

decided to replace the basic mirror 1.25 diagonal that came with the C8 Edge HD. A mystery why a scope with high end optics has a basic mirror diagonal - defeats the purpose of getting an HD visual.

My issue with this 'twist lock' is that it really is more of a 'screw on' where you need to turns it a lot of revolutions to get the collar tight on the eyepieces. Moreover, you REALLY have to tighten the attaching collar to the back of the OTA otherwise it is regularly loosening, especially with with 2" eyepieces. My fear is overtightening/stripping the 
threads to stop the diagonal from flopping around. 

THAT IS A CHEAP DESIGN.

Is the actual mirror visual a marked improvement from the original ? - hard to say. I bounced back and forth using the original 1.25 eyepiece - no discernible improvement in light/clarity.

On the fence. Best comment is "OK, not WOW".

OK not WOW

Perfect fit on my sct and the feel is solid.  I was worried about the weight of a 2? diagonal upgrade but it?s a little lighter that some of the others.  My Nexstar seems fine with it.  
My 1.25 eyepieces fit nicely in the adapter and my 2? eyepiece fits perfectly. Love the higher visibility orange lock collars. Overall pleased with the shipping and product.

Quality product as advertised.

I was very impressed with the fit and finish of this Celestron telescope diagonal. This allows 2 inch eyepieces to be used, which dramatically increases the quality of astronomical viewing. I have already recommended this necessary upgrade to fellow astronomy club members.

Celestron 2 inch telescope diagonal review.

Love the twist-lock mechanism for holding my eyepieces and the eyepieces stay secure. No moving or sliding around using the little thumb screws, which always seem to strip out after awhile. The dielectric is a huge upgrade over a standard diagonal.

Image is much brighter and clearer than standard stock diagonal

A must upgrade for your telescope

Excellent piece - very fine craftsmanship and makes swapping pieces very fast.

And yes, you can use it with the focal reducer, as well. Don't need to listen to those that say there is no purpose for it - it actually helps get the cheap sv305 to take some ok shots.

Excellent addition to my celestron

Very well constructed

Mirror quality great, and overall materials  used high quality.

Celestron Dielectric Star Diagonal 2"

very well built love the twist lock still waiting for good skys to really take for test drive

great for sct

I bought this to replace the diagonal that was missing from a used Celestron 9.25 CPC HD scope that I bought. Wow, I am spoiled now!  It is more convenient to change eyepieces now than before. It is a nice upgrade, and I'm glad I bought it.

Nice Upgrade

Upgraded my Evo 9.25 with this, making it much quicker and easier to attach eyepieces. The thumbscrews on the stock diagonal interfered with a couple of my eyepieces but this one fixes that problem. Eyepieces now feel more securely attached as well. Best money spent  so far.

Great upgrade for evolution

Didn't get a chance to use it yet. Seems to be well made. Fits eyepieces well too.

Celestron Dielectric Star Diagonal, 1.25" with Twist-Lock

Key Features

Protect your gear with Adorama Protect.* Learn more

Celestron Dielectric Star Diagonal, 1.25" with Twist-Lock

Save 5% Every Day†

Key Features

Protect your gear with Adorama Protect.* Learn more

Save 5% Every Day^†