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William Optics 2" 99% Dielectric Dura Bright Carbon Fiber Mirror Diagonal for Refractors

4.9 (19 Reviews) Read Reviews Write Review
Brand William Optics
Part Number D-DIG2D-C-DB
Availability available

Product Info

Manufacturer Description

Introducing the New William Optics 2015 Dura-Bright diagonal - a dramatic step forward in the evolution of mirror diagonals!

This 90° 2"mirror-type star diagonal has a Dura-Bright 12mm thick mirror, 1/12 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. Features a 2" nosepiece for insertion into refractor telescopes and other 2" focuser barrels.

Dura-Bright features 100% real carbon fiber side plates that add that touch of class your scope deserves.

The WO 2" Dura-Bright Diagonal was designed with several unique features to provide optimum performance and years of use.

Top-Notch Performance and brightness

  • Dielectric coating allows 99% reflectivity.
  • High precision 12mm thick mirror substrate flat for optimal image stability.
  • Polished to 1/12th wave accuracy.
  • Accurate design guarantees constant alignment. No further alignment needed.

Meticulous Craftsmanship

  • 2" to 1.25" eyepiece adapter included.
  • Lock screw for eyepiece/adapter.
  • Big, knurled thumbscrews are easy to turn even with gloves on.
  • Threaded for 48mm filters.

Strikingly Beautiful

  • Patented, elegant design.
  • High-quality machining out of the best aluminum.
  • Internal anti-reflection baffling for highest contrast.
  • Real Carbon Fiber side plates

Superbly Constructed

  • Compression rings (both on diagonal and adapter) to prevent barrels from marring.
  • Internal safety stop prevents 2" barrels from hitting the mirror.
  • Designed for high-end scope such as FLT-98, FLT-110 and FLT-132.

Additional specifications

  • Weight (without 1.25" adapter) = 15.2oz.
  • Weight (with 1.25" adapter) = 1lb-2.1oz.

Reviews

4.9 (Based on 19 Reviews) 95% of reviewers recommended this product.
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    1. Guest

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      Review by CHAMBEL L.
      1552120530
      Mar 9, 2019

      5.0 Perfect

      Pros:

      Cons:

      Comments:

      Quality and finish for this accessory.I rediscover the deep sky.Use on CPC 1100

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    2. Guest

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      Review by Larry S.
      1536926290
      Sep 14, 2018

      4.0 Well made unit

      Pros:

      Cons:

      Comments:

      Super clear compared to stock Celestron 1.25 in. diagonal. Superb construction quality. A little tricky to mount the first time because the mating ring fully threaded onto telescope rear cell does not cinch the unit up tight to the scope. You need to actually rotate the body (must also have threads on barrel into ring) to snug it up. Good solid connection once snugged, don't see any visible marring to rear cell. Mildly concerned for possible seizing, but so far no problem. I have taken it off and replaced it several times to put in the focal reducer between it and rear cell. Not sure what good the thermometer is, but it works.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    3. Guest

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      Review by Steve K.
      1508285559
      Oct 17, 2017

      5.0 Williams 2" SC Dielectric diagonal

      Pros:

      Cons:

      Comments:

      An exceptional value for a great Diagonal!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    4. Guest

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      Review by Travis T.
      1499523764
      Jul 8, 2017

      5.0 WO 2" dialectric diagonal

      Pros:

      Cons:

      Comments:

      Bought this for my little 72mm ED refractor. After having it out 1 time so far on a clear night looking at the moon, Jupiter, & Saturn. I am really pleased at the clarity and light transmission from this diagonal. Seems to be well made for the value and it looks good on the scope! Keep in mind that this is my first diagonal (and scope) that I've ever owned...

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    5. Guest

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      Review by Craig
      1491927485
      Apr 11, 2017

      5.0 What A Difference

      Pros:

      Cons:

      Comments:

      I'm very new to astronomy and once I bought the Celestron 8SE I had to get a bigger diagonal. The 1.25" OEM is a fine piece but this William Optics diagonal is truly the difference between day and night. What a difference! This diagonal is wonderfully machined and the carbon sides are a nice touch; you'll have to rebalance your scope after mounting this diagonal due to it's weight; very solid and nice!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    6. Guest

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      Review by Ed of FL.
      1475280000
      Sep 30, 2016

      5.0 Excellent diagonal at a reasonable price

      Pros:

      Quality Lenses,Easy to Use,Compact,Strong Construction

      Cons:

      Comments:

      I purchased this unit to replace the stock diagonal that came with one of my scopes. Much better in every way!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    7. Guest

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      Review by Opticaljunkie of Melbourne.
      1454630400
      Feb 4, 2016

      5.0 Great quality

      Pros:

      Easy to Use,Accurate,Quality Lenses,Lightweight,Strong Construction,Compact

      Cons:

      Comments:

      Needed a 2" diagonal, this was excellent value for money and top quality

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    8. Guest

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      Review by wingman astronomer of El Paso, TX.
      1444435200
      Oct 9, 2015

      5.0 Perfect for Celestron 9SE

      Pros:

      Easy to Use,Strong Construction,Accurate,Quality Lenses,Compact

      Cons:

      Comments:

      The stock diagonal that comes with the 9SE is unacceptable and limited. This diagonal is not only well built and easy to install it is the best upgrade, besides buying a TeleVue eyepiece, for your telescope, that you can make. This diagonal will clear the base of the robotic arm so you can view stars that are straight up. An Ethos TeleVue eyepiece fits perfect in it. It really is a beautiful work of art with the carbon fiber and solid construction, not to mention the light transfer rated at 99%. You have to buy this.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    9. Guest

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      Review by wingman astronomer of El Paso, TX.
      1435622400
      Jun 29, 2015

      5.0 The only Diagonal you'll need

      Pros:

      Strong Construction,Easy to Use,Accurate,Quality Lenses

      Cons:

      Comments:

      If you are looking for a diagonal replacement for the cheap flimsy one that came with your 8SE like I was, then buy this one. Not only is it built solid but it does add brightness to the stars and planets. Also, a BIG plus is that it will clear the bottom of the 8SE mount, so if you want to observe objects that are straight up then you can!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    10. Guest

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      Review by mike h of Yukon, PA.
      1427500800
      Mar 27, 2015

      5.0 Great

      Pros:

      Lightweight,Accurate,Strong Construction,Easy to Use,Quality Lenses

      Cons:

      Comments:

      Can't see a difference between this and a much more expensive diagonal that I have ..great job!!!!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    11. Guest

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      Review by Strehlboy of Palm Bay, FL.
      1427500800
      Mar 27, 2015

      5.0 One super Diagonal!

      Pros:

      Compact,Strong Construction,Easy to Use

      Cons:

      None

      Comments:

      This was a gift for my nephew, and is working on a 4 inch refrator. The tells me stars are pinpoint, clear and actually may increase the magnitude of stars visible in this scope. This diagonal is a winner.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    12. Guest

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      Review by Nhopa of Surprise, AZ.
      1424476800
      Feb 20, 2015

      5.0 Good value for an outstanding optics

      Pros:

      Quality Lenses,Lightweight,QUALITY MIRROR,Strong Construction,Easy to Use

      Cons:

      Can't Think Of Any Cons

      Comments:

      This equipment was a great upgrade replacing my former 1-1/4" star diagonal. Now I will be able to change my eyepieces to the 2" size. Images are much brighter. Good investment.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    13. Guest

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      Review by Starman703 of Acworth,GA.
      1413590400
      Oct 17, 2014

      5.0 Quality built

      Pros:

      Accurate,Strong Construction,Quality Lenses,Easy to Use

      Cons:

      Heavy

      Comments:

      This finally allowed me to use 2in eyepieces on my trusty C8. What sold me was a great price and very FAST shipping. Great deal as usual from Agena!

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    14. Guest

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      Review by Tony from NM of Corrales, NM.
      1408233600
      Aug 16, 2014

      5.0 Excellent quality diagonal

      Pros:

      Accurate,Easy to Use,Lightweight,Strong Construction,Quality Lenses

      Cons:

      Comments:

      I trust William Optics' equipment and this diagonal does not disappoint. I purchased this diagonal for use with my WO GTF-81 and it works beautifully.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    15. Guest

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      Review by South Shore Stargazer of NY State.
      1408147200
      Aug 15, 2014

      5.0 Best value in a dielectric diagonal

      Pros:

      Lightweight,Strong Construction,Easy to Use,Accurate,Compact

      Cons:

      None

      Comments:

      I love this diagonal. Bright, well crafted, good brand, great warranty, excellent price.
      What's not to like? I use it on my SV102 Stellarvue.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    16. Guest

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      Review by Jeff the tinkerer of Zionsville, IN.
      1401494400
      May 30, 2014

      5.0 A necessity for WO GT81/GTF81

      Pros:

      Lightweight,Easy to Use,Strong Construction,Accurate

      Cons:

      Comments:

      WO GTF81 doesn't have enough back travel for visual observation on its own, so a diagonal or quite long extension is necessary. Bevel on OTA side makes for secure attachment. Looks good too.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    17. Guest

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      Review by mark of maryland.
      1401494400
      May 30, 2014

      5.0 Really clear

      Pros:

      Cons:

      Comments:

      Really excellent build. Well worth the investment. Will definitely last for many years

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    18. Guest

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      Review by 0ctane of Zionsville, IN.
      1395878400
      Mar 26, 2014

      5.0 Solid, quality construction

      Pros:

      Strong Construction

      Cons:

      Comments:

      Does what it is supposed to do. It has some heft to it, but I don't have any other diagonals to compare it to.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

    19. CosmicLugNut

      CosmicLugNut Member

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      Review by CoosmicLugNut of SW Indiana.
      1386374400
      Dec 6, 2013

      5.0 Precision Optics/Affordable/Impressive

      Pros:

      Lightweight,Accurate,Easy to Use,Strong Construction

      Cons:

      None

      Comments:

      The big, knurled thumbscrews are easy to turn even with gloves on. I find the WO 2" Dura-Bright Diagonal design quite elegant and the precise machining guarantees constant alignment. Internal anti-reflection baffling guarantees the highest contrast possible and most importantly the impressive WO Dura-Bright Diagonal looks great on my grab and go rich field ST80 Achromat. I was so impressed with the fit and finish I bought a second one for my Omni XLT120. WO has delivered an excellent 2-inch diagonal at a price point everyone should be able to afford.

      Bottom Line: Would you recommend this item? No
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

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