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William Optics 1.25" SPL Series Eyepiece - 12.5mm

5.0 (1 Reviews) Read Reviews Write Review
Brand William Optics
Part Number E-SPL12.5
Availability available

Product Info

Manufacturer Description

William Optics is proud to introduce the SPL (Super Planetary Long eye-relief) eyepieces. This new Planetary Eyepiece series is designed for users with needs of a high-power, sharp and contrasty views for planetary observations. The long eye relief is a bonus for people with eyeglasses and for people who do not want to strain their eyesight during observing sessions.

High Quality Optical Lens

  • Special glasses and perfect multi-coatings make the optical performance of SPL eyepieces amazing in almost any telescope. A very well corrected field of view, free from optical aberrations allows you to finally enjoy planets as they deserve.
  • Good transmittance and excellent color rendition will allow you to enjoy planetary details you had missed so far.
  • Leave ghosting and flares to other eyepieces: your William Optics SPL will not disappoint you.

High Power and High Contrast

  • Available in three focal lengths, 3mm, 6mm, and 12.5mm, these eyepieces will satisfy any power requirement. Easy to barlow, they will yield amazing results even at the highest powers (provided that atmospherical conditions and your telescope can hold such high powers!).
  • Great contrast and sharp to the edge.
  • Distortion-free extra details is not a miracle: it all goes down to quality construction and design. SPL give you just what you always wanted.

Long Eye Relief

  • All three focal lengths boast very long eyerelief for maximum view comfort even for eyeglass wearers.
  • Mechanically beautiful and functional tapered barrel.
  • Blackened lens edges and flat black paint in the barrel to minimize sources of potential reflections.

Excellent value

  • The very competitive price of these planetary eyepieces will encourage you to get the whole series to add to your collection!


5.0 (Based on 1 Reviews) 100% of reviewers recommended this product.
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    1. Guest

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      User Notes:
      Review by Marcelo the beginner of Brazil.
      Feb 27, 2014

      5.0 Excellent eyepiece!


      Strong Construction,Accurate,Quality Lenses



      I'm a beginner amateur and this is my first "serious" eyepiece. I own an Mak 90mm from Skywatcher that came with a Wide-angle 25mm (ok EP) and a 10mm Plossl (junk!).
      I have seen a few times on some 10" and 12" SCT with 2" eyepieces at star parties from the hardcore guys, and a Televue Panoptic is my benchmark.
      This eyepiece has a huge view! It's almost as looking through an window instead of a keyhole! Image is sharp and colors seems true. I can not see fringes, rings or other aberration. It states long-eye relief, but as I approach my eye to the eyecups, I can see more and more.
      This is totally better than the other William Optics SWAN 9mm I bought: sharp, easy to focus, nice "spacewalk" view. The 9mm is not very sharp (I know it approaches the theoretical limit of my Mak 90mm, but I never got a single detailed view on it!) and although it's stated as a 72 degree (vs 58 for the SPL), the view is so small (I now their true field should come near).
      I like this EP very much. If only they offered larger aperture (or if I ever buy a larger telescope), I'd buy the other sizes...

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

      This review was provided courtesy of AgenaAstro.com

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      Apparent Field of View 55°
      Barrel Size 1.25" (31.7mm)
      Bolt Case Included Yes - Free Agena Eyepiece Container
      Bolt Case Size Agena 52x80mm
      Coatings Fully Multi-Coated
      End Caps 2
      Eye Relief by Design 20mm
      Focal Length 12.50mm
      Lens Elements 7
      Lens Groups 4
      Blackened Lens Edges Yes
      Manufacturer William Optics
      Eyepiece Focal Length 10.1mm - 15mm
      Eyepiece Field of View 51 - 60 degrees
      Eyepiece Series William Optics SPL
      Barrel Type Tapered barrel
      Filter Threads Standard 1.25" Filter Thread (M28.5 x 0.6)
      Eyepiece Weight 5.29oz (150g)