William Optics 1.25" DURA-BRIGHT Dielectric Diagonal

William Optics 1.25'' DURA-BRIGHT Dielectric Diagonal


In stock - Shipped 1-2 working days.

Model:  WOdielectric125
Part Number:  D-125D-C-DB
Brand:  William Optics

Offers a noticeable improvement in brightness, contrast and overall sharpness when compared to budget diagonals!

  • Dura-Bright thick mirror and dielectric mirror coatings for 99% reflectivity.
  • Precision 1/12 lambda surface accuracy.
  • 12mm-thick mirror substrate.
  • Threaded to accept 1.25" filters.
  • Compression ring to prevent barrels’ marring.
  • Internal safety stop prevents 1.25” barrels from hitting the mirror.

Introducing New 2014 model William Optics Dura-Bright diagonal - a dramatic step forward in the evolution of mirror diagonals! This 90° 1.25"mirror-type star diagonal has a Dura-Bright thick mirror and dielectric mirror coatings for 99% reflectivity which provides higher contrast and resolution during critical planetary, lunar and binary star observations.

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

The WO 1.25" 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
• Lock screw for eyepiece/adapter.
• Big, knurled thumbscrews are easy to turn even with gloves on.
• Threaded for 1.25" Filters.

Strikingly Beautiful
• Patented, elegant design.
• High-quality machining out of the best aluminum.
• Internal antireflection 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 scopes.

Product Specifications

ReflectivityUltra High Dielectric 99% reflectivity.
MirrorPrecision 1/10 lambda surface with 12mm thickness mirror for best quality.
Accessories2"- 1.25" adapter with brass clamping ring,includes
MeasurementsInside diameter (48mm): threaded to fit a variety of filters.
WeightWeight : 210g

William Optics 1.25" DURA-BRIGHT Dielectric Diagonal Questions & Answers

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Average Rating (5 Reviews):  
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Rating (max 5):  
Great Product
Wednesday, 13 June 2018  | 

Great Product

Rating (max 5):  
Great product.
Tuesday, 6 February 2018  | 

Great product, great service! But I wish they'd stop asking for feedback every time I buy something!!

Rating (max 5):  
Solid design
Monday, 1 September 2014  | 

This diagonal looks good and feels even better. Compared with a stock Skywatcher diagnoal, the build quality is far superior. I used this diagonal with a Celestron X-Cel LX (25 mm) and the view was crisp and flat to the very edge of the FOV.

Rating (max 5):  
Don't be deceived!
Thursday, 11 October 2012  | 

People look at this diagonal and assume that - due to its hefty build - it must be of high quality.

Unfortunately it has two problems which are serious enough to strike it off your wish list:

1) Firstly, the internal safety-stop actually obstructs light - vignetting the edge-of-field on super-wide eyepieces.

2) The safety-stop - and some other parts - have shiny surfaces which casts glancing light reflections into the eyepiece, causing annoying glare on the moon and bright stars.

Best choose something else.

FLO Response: There has been no attempt at deception Jeremy, please contact us with your purchase details so we can arrange a full refund

Rating (max 5):  
Very high quality diagonal
Tuesday, 31 May 2011  | 

I've often heard it said that a diagonal upgrade gives you nebligible optical improvement, but that doesn't mean it isn't worthwhile.

You may not notice a significant difference observing with it, but what matters is build quality. A well-made diagonal holds eyepieces more securely and accurately in the optical train.This diagonal is extremely well made, and a real joy to use. It's got everything right: tapered barrel for a secure fitting, very stable body with carbon fibre panels, excellent compression ring holder with lovely large thumbscrew, lightweight, optically superb, and, very importantly, a perfectly well-justified pricetag, which means it's well-worth it even if you can't see any difference!

I would see no reason to spend more on a 1.25" diagonal.

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