Celestron 90° Dielectric Star Diagonal with Twist-Lock (1.25")

BH #CEDSDTL125 • MFR #93571
Celestron 90° Dielectric Star Diagonal with Twist-Lock (1.25")
Key Features
  • 1.25" Nose Piece and Holder
  • BK7 Glass, Diffraction-Limited Optics
  • 58-Layer Dielectric Coatings
  • Over 99% Reflective Mirror Surfaces
Enjoy better views through your telescope and change eyepieces and accessories faster and more easily with the Celestron 90° Dielectric Star Diagonal. The diagonal has a 1.25" nosepiece and holder to make it compatible with the most popular size of gear from eyepieces to Barlows, filters, and a near-infinite array of accessories.
In Stock
$144.95
Save the Tax with the credit card. 
Protect your Gear
Add a protection plan from $23.00

True Know-How

Ask Our Experts

866.264.7509

Celestron 93571 Overview

Enjoy better views through your telescope and change eyepieces and accessories faster and more easily with the Celestron 90° Dielectric Star Diagonal. The diagonal has a 1.25" nosepiece and holder to make it compatible with the most popular size of gear from eyepieces to Barlows, filters, and a near-infinite array of accessories.

Designed with diffraction-limiting optics, its BK7 mirror is treated with 58 layers of dielectric coatings that produce a reflective surface greater than 99% so more incoming light makes it to your eye—this is especially important when viewing dim deep-sky objects where every photon of light is important.

For the eyepiece holder side of the diagonal, Celestron eschews convention and replaces the ubiquitous three thumbscrews to tighten the interior compression ring with a twist-lock. Utilizing a twist-lock not only makes swapping your eyepieces and accessories faster and easier, it properly centers the eyepiece and maintains proper optical alignment. The nosepiece is outfitted with standard filter threads so you can install your favorite filter—like a moon, nebula, or light pollution—without having to move it from one eyepiece to another as you go about your observation sessions. The aluminum housing has a black anodized finish, and the interior is painted flat black with blackened threads to reduce reflections.

UPC: 050234935715

Celestron 93571 Specs

Eyepiece Barrel Diameter1.25"
MaterialsGlass: BK7
Housing: Aluminum
Dimensions4.5 x 3.5 x 2.0" (114.3 x 88.9 x 50.8mm)
Weight7.5 oz (212.6 g)
Packaging Info
Package Weight0.665 lb
Box Dimensions (LxWxH)5.3 x 4.4 x 3.7"

Celestron 93571 Reviews

Major Improvement!

By Andrew
Rated 5 out of 5
Date: 2021-08-16

Finally had an opportunity to get out my telescope over the weekend and use the new twist lock 90 degree diagonal. The twist lock is excellent. So much easier than fumbling for the little screws that you have to finger tighten. The only negative I can say is that the twist lock needs to be tightened a lot if you have a variable eye-piece. I have a Celestron 8-24mm lens and I needed to tighten the twist lock quite a bit. Honestly, it is a minor inconvenience if I have to hold the lens when I adjust it. The 1.25 Twist Lock Celestron 90 Dielectric Star Diagonal is a huge improvement over the stock diagonal on the Celestron Nexstar 8SE .

Yes, brighter

By David
Rated 4 out of 5
Date: 2020-10-14

Reading many reviews on star diagonals I wasn't sure whether it would be any brighter than the stock prism on my Celestron C5. Well, it is. I didn't have any trouble adapting to the mirror reverse image. I don't know if a dielectric mirror is any better than an aluminized mirror without having the latter on hand to test.

Great looking and performing !

By Darren
Rated 5 out of 5
Date: 2020-09-30

Celestron 90° Dielectric star diagonal with twist lock is a top performer. Boasting rich clear images and incredible detail you'll wonder how you ever did without it! A great addition to your astronomy collection.

Nice clean view

By David
Rated 4 out of 5
Date: 2020-09-26

Much more comfortable viewing at a right angle on my C5. It is big but not heavy. It is strange that it also can take 2 eyepieces and then crush down the view to 1.25 But I think that is for them folks with 2 eyepieces laying around.

Best thing I've bought.

By Kevin
Rated 5 out of 5
Date: 2020-08-24

I bought this to see if I could improve the view on my celestron 102mm refractor. The image is crystal clear and the ease of a simple twist to lock the eyepiece in is a welcome bonus. The build is very impressive and screams quality. It is simple to use, works well and value for money. Big thanks to the guys at B&H outstanding all the way...

Much Improved

By Keith
Rated 5 out of 5
Date: 2020-08-21

Have the 6 Celestron Advanced VX Refractor on Go-To mount and was very happy until I replaced the standard plastic diagonal that came with scope with this one. Much improved vision, images are clearer and sharper. The twist lock is a lot easier to use in the dark as well. Very pleased with this purchase. B&H is very easy to order from and products shipped immediately when in stock.

NECESSARY Upgrade!

By Matthew
Rated 5 out of 5
Date: 2021-06-07

This is a perfect upgrade and a must have for my SCT scope. It boasts High quality build and sleek design. This is a necessary upgrade from the stock diagonal that came with my scope!

Excellent Diagonal

By Mahesh
Rated 5 out of 5
Date: 2021-03-28

The diagonal is a very good quality product from celestron. BandH order processing and shipping was fantastic too.

See any errors on this page? Let us know

YOUR RECENTLY VIEWED ITEMS

Close

Close

Close