See what William Paolini, noted amateur astronomer and author of Choosing and Using Astronomical Eyepieces, had to say about this eyepiece on CloudyNights.com.
- “This is a really sweet eyepiece, has a nice eyecup function, the dual skirt is very elegant so that with it on it looks like a native 2" EP and with it off it looks like a native 1.25" EP, and it is surprisingly killer on planets and sharp to the edge. Since this is a good higher power eyepiece for the little 60mm [f/16.7 refractor], I decided to use it. The WO 9mm 101 showed the entire disk with room to spare at 111x and was completely mesmerizing! The BIG 101 degree view from this eyepiece made me feel like the scope was similarly a BIG performer, taking away any notion that is was anything but big performer.”
- "I put this eyepiece in my f/8 [telescopes] as well and again sharp to edge. I've not tried it side by side with the Explore Scientific 9mm, but from memory this one seemed better edge corrected. Again though, the build is just so thoughtful as dual skirted eyepieces are usually cludgy looking...this one is quite elegant...only one of the 100's out there that I really liked aesthetically and functionally (the build)."
New from William Optics - Offered at a special introductory price (while supplies last)!
- William Optics 9mm 101-deg Extreme Wide Angle (XWA) eyepiece
- Dual 1.25" and 2" barrel format
- Comfortable 15mm eye relief
- Twist-up eyecup
- Fully multi-coated optics (9 elements in 6 groups) with blackened lens edges
- Made in Taiwan from Taiwanese, Chinese, and Japanese components
- 1.25" eyepiece with 2" sleeve. 2" barrel uses a unique / innovative male 1.25" filter thread on the inside to connect to the female filter thread on the 1.25" barrel.
- 1.25" eyepiece: 1lb-4.6oz
- 2" sleeve: 2.3oz
- 2" eyepiece: 1lb-6.9oz
- 1.25" eyepiece (with eyeguard recessed): 146.8mm (5.78")
- 2" eyepiece (with eyeguard recessed): 150.2mm (5.91")
- Eyeguard can extend by: 7.5mm (0.3")
- Maximum width (excluding end caps): 65mm (2.56")
|Apparent Field of View||101°|
|Barrel Size||1.25" (31.7mm) and 2" (50.8mm)|
|Bolt Case Included||Yes - Free Agena Eyepiece Container|
|Bolt Case Size||Agena 85x120mm|
|Height (with Eye Guard)||See item description|
|Eye Lens Diameter||27.7mm|
|Eye Relief by Design||15mm|
|Filter Threads||Standard 1.25" (M28.5 x 0.6) and 2" (M48 x 0.75) Filter Thread|
|Rubber Eye Guard||Twist-up Eyecup|
|Eyepiece Weight||22.90oz (649.20g)|
|Blackened Lens Edges||Yes|
|Eyepiece Focal Length||5.1mm - 10mm|
|Eyepiece Field of View||Over 80 degrees|
|Eyepiece Series||William Optics XWA|
|Barrel Type||With safety undercut|