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.

1.25" Nose Piece and Holder    BK7 Glass, Diffraction-Limited Optics    58-Layer Dielectric Coatings    Over 99% Reflective Mirror Surfaces    Twist-Lock Maintains Optical Alignment    Black Anodized Aluminum Housing    Filter Threads on Nosepiece

Related Questions and Answers

Q: 1. IS THERE FREE SHIPPING TO MESA, AZ 85205?

A: Yes there is. If you add the item to your cart, and type in your ship to Zip Code it will show you the Shipping Options.

Q: 2. Can this product attach to the Sky-Watcher Evostar ED APO 72mm f/5.8 Refractor Guidescope?

A: The Celestron 90° Dielectric Star Diagonal with Twist-Lock (2") BH #CEDSDTL2 • MFR #93573 will attach to the Sky-Watcher Evostar ED APO 72mm f/5.8 Refractor Guidescope

Q: 3. Is it work with celestron nexstar 8se? Is it necessary to buy any additional adapter?

A: No it will only attach toa 2"thread which the 8SE does not have.

Q: 4. Can this product be attached to the NextStar 6 SE?

A: Yes, you can use the Dielectric Star diagonal 2" item # 93573. However, keep in mind that the opening of the Nexstar 6 is smaller than an 8 inch telescope and you will not get the full benefit of the 2" wide view.

Q: 5. What is the transmissive efficiency of the 93527 diagonal mirror?

A: The MFR needs to be contacted for this answer.

Q: 6. Is the 2”/1.25” model works in a nexstar 8se? Could I use an 2” eyepiece with this? Use a 2” eyepiece is better than an 1.25”?

A: Yes, its 100 % Compatible. Yes, it accepts both size eyepieces. A 2" eyepiece does offer more features over a smaller eyepiece.

Q: 7. How does it change the up/down, left/right view of the image?

A: The Celestron 90° Dielectric Star Diagonal with Twist-Lock (1.25") does not have the ability to change the view. It is not an erect image diagonal.

Q: 8. Just purchased the iOptron Photon 6". Not using the SCT adapter, will this attach to the scope's focuser w/o a visual back?

A: The Celestron 90° Dielectric Star Diagonal with Twist-Lock (2") can attach directly to the focuser of the iOptron Photron 6" via its 2" nosepiece. If not achieving focus, one can use the iOptron extension rings to get the correct backfocus distance.

Q: 9. Will this fit a Celestron NexStar Evolution 6". should I just get the the other 1.25" Dielectric Diagonal(with the orange Twist-lock)

A: This will also work on the Evolution 6

Q: 10. Can the 1.25" eyepiece adapter included be used with 2" filters? Will they fit? So we can use 2" filters with 1.25" eyepieces with this 2" diagonal and 1.25" adapter.

A: The 2 inch filters will fit onto the 2 inch eyepiece adapter ..