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Pentax XW Wide Field Eyepiece 1.25"

Price:  £254.00 (Inc. 20% VAT)Earn 254 Loyalty Points
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Model:  xw3.5
Brand:  Pentax

  (1 Review)
Pentax XW Wide Field Eyepiece 1.25''
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These proprietary wide field eyepieces use six to eight lenses in unique four to six group designs to achieve a wide 70-degree apparent field of view. They run the full gamut of magnifications, from very low power to very high power. Each has an exceptionally long 20mm eye relief that gives fully unvignetted views for those with severe astigmatism who must wear eyeglasses while observing.

Rotating the rubber-rimmed eyecup raises and lowers it to precisely customize the eyecup height to match your eyesight and eyeglass use. The chrome barrel of each eyepiece is threaded for standard light pollution and color filters. A safety groove cut into the chrome barrel engages the thumbscrew of the focuser to keep the eyepiece from falling if the thumbscrew accidentally loosens during use. All are multicoated on all air/glass surfaces, using proprietary Pentax Super Multi-Coatings (SMC). The edges of the lenses have been blackened to eliminate internal reflections for better contrast.

All use high-refraction, low-dispersion lanthanum (rare earth) lenses to minimize chromatic aberrations and astigmatism. They can be used for all types of observing, with all telescope types, and are optically corrected for use with focal ratios as fast as f/4.

They have good contrast and excellent center to edge sharpness, with very little ghosting. They are weatherproof to JIS Class 4 standards (which means that dew accumulation won’t cause a problem, although full submersion in a bucket of water is a no-no). Each eyepiece comes with plastic dust caps for the barrel and eye lens and a bolt-type plastic container for storage.

They are protected against flaws in materials or workmanship by a lifetime warranty, a rarity in telescope equipment.

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20mm XW Review
Saturday, 21 June 2014  | 

Bought one of these 10 days ago, and of course, new Kit is a "Cloud Magnet". Managed to get first light 20/6/2014 at the York Astronomical Society Observatory.
Absolutely "Blown Away" by this eyepiece. Being mainly a Lunar & Planetary Observer, I have always been of fan of traditonal Orthoscopic eyepieces, nothing can quite match them for sharpness across the field of view so a new eyepiece in my book had to be good to beat one of these.
I read loads of reviews on Cloudy Nights, and Stargazerslounge Forums before parting with my hard earned cash.
I chose the 20mm because it is the longest focal length available for my Mak 180 PRO.
Saturn despite its low elevation was more contrasty and I managed to follow the Cassini Division almost right across the front part of the planet - something I have never been able to do in 30 years of observing.
Looking at M13 I saw more stars further out in the outer regions of the cluster than I had seen before and they were the tiniest of points of light.
The Ring Nebula M57 was a revelation in this eyepiece - mottling in the central region of the nebula.

The eyepiece is very comfortable to use having fantastic eye relief, and it my opinion "Turns everything up quite a FEW NOTCHES" in performance.
Not the cheapest eyepiece, but VERY well worth paying for.
A couple more are on the shopping list in the near future.
I have used loads of other eyepieces over the years inc. superb Vixen Lanthanums and Tele-Vue Plossls and the Pentax is superior to them all.
Pentax have certainly lived up to their reputation.

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