Pentax 2" SMC XW40-R Eyepiece - 40mm
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- Designed for use with astronomical telescopes with 2" focusers/eyepiece holders
- Weatherproof construction for greater durability
- Features high-grade Lanthanum glass with high refraction and low dispersion
- Original multi-coating and special coating on the laminated surfaces effectively reduce flare and ghosting, achieving extremely high light transmission performance
- A male M48x0.75 thread under the removable eyecup allows attachment of external imaging adapters (not included)
70% Apparent Field of View, 20mm Eye Relief, plus Weatherproof Body for Multi-Application Viewing
Clear, Comfortable Viewing Assured by 70° Apparent Angle of View and 20mm Eye Relief
All SMC Pentax XW-series eyepieces feature an extra-wide 70-degree apparent angle of view and an extra-long 20mm eye relief to deliver an exciting, wide-perspective image. Also features an adjustable twist-up eye cup.
High-Grade Optics for Exceptional Image Quality
The high-performance XW-series optics incorporates high-refraction, extra-low-dispersion lanthanum glass elements to produce a well-balanced image with minimal aberrations. It is particularly designed to reduce the disturbing blackout effect by effectively compensating the spherical aberration of the pupil.
Pentax-Original Multi-Layer Coating for Outstanding Light Transmission Efficiency
All lens surfaces that come in contact with air are treated with original multi-layer coatings, while all laminated surfaces are treated with an innovative partial coating to offer the light transmission efficiency of more than 90 percent (an astonishing 96 percent at 550nm) over the visible light spectrum.
Advanced Light-Shielding Technology for Improved Image Contrast
Thanks to Pentax’s advanced computer simulation technology, the XW series features a light-shielding diaphragm at the most effective position to drastically reduce internal reflections for a brighter, higher-contrast image.
Weatherproof Construction for All-Weather Viewing
The XW series features JIS Class 4 weatherproof construction, making it possible to use it in drizzle or under night dew. However, please note that the XW-series eyepieces are not designed for underwater use and should not be submerged under water.
American-Standard Eyepiece Sleeve and Built-In Adapter-Mounting Screw
The XW series features the American-standard 50.8mm (2") barrel for smooth, easy installation on telescopes. When the rotatable eyecup is removed, it also offers an adapter-mounting screw/thread (48mm in diameter with a 0.75mm pitch).
| Free Shipping Graphic | Free US Shipping |
|---|---|
| Eyepiece Series | XW |
| Focal Length | 40mm |
| Barrel Size | 2" (50.8mm) |
| Apparent Field of View (Mfg Specified) | 70° |
| Eye Relief (Designed) | 20mm |
| Filter Threads | Standard 2" Filter Thread (M48 x 0.75) |
| Coatings | Fully Multicoated |
| Lens Elements | 6 |
| Lens Groups | 5 |
| Barrel Type | With safety undercut |
| Protective Plastic Storage Container | Yes - Manufacturer Supplied |
| Height (With Eyeguard Extended) | 117mm / 4.61" |
| Maximum Width | 76mm / 2.99" |
| End Caps | 2 |
| Rubber Eye Guard | Yes |
| Weight | 26.1 oz / 740 g |
| Country of Manufacture | Japan |
| Misc. Information |
Water proof: Yes (JIS Class 4) Weather protection: Yes |
| Hide Found a better Shipped Price on Frontend? | No |
- Designed for use with astronomical telescopes with 2" focusers/eyepiece holders
- Weatherproof construction for greater durability
- Features high-grade Lanthanum glass with high refraction and low dispersion
- Original multi-coating and special coating on the laminated surfaces effectively reduce flare and ghosting, achieving extremely high light transmission performance
- A male M48x0.75 thread under the removable eyecup allows attachment of external imaging adapters (not included)
70% Apparent Field of View, 20mm Eye Relief, plus Weatherproof Body for Multi-Application Viewing
Clear, Comfortable Viewing Assured by 70° Apparent Angle of View and 20mm Eye Relief
All SMC Pentax XW-series eyepieces feature an extra-wide 70-degree apparent angle of view and an extra-long 20mm eye relief to deliver an exciting, wide-perspective image. Also features an adjustable twist-up eye cup.
High-Grade Optics for Exceptional Image Quality
The high-performance XW-series optics incorporates high-refraction, extra-low-dispersion lanthanum glass elements to produce a well-balanced image with minimal aberrations. It is particularly designed to reduce the disturbing blackout effect by effectively compensating the spherical aberration of the pupil.
Pentax-Original Multi-Layer Coating for Outstanding Light Transmission Efficiency
All lens surfaces that come in contact with air are treated with original multi-layer coatings, while all laminated surfaces are treated with an innovative partial coating to offer the light transmission efficiency of more than 90 percent (an astonishing 96 percent at 550nm) over the visible light spectrum.
Advanced Light-Shielding Technology for Improved Image Contrast
Thanks to Pentax’s advanced computer simulation technology, the XW series features a light-shielding diaphragm at the most effective position to drastically reduce internal reflections for a brighter, higher-contrast image.
Weatherproof Construction for All-Weather Viewing
The XW series features JIS Class 4 weatherproof construction, making it possible to use it in drizzle or under night dew. However, please note that the XW-series eyepieces are not designed for underwater use and should not be submerged under water.
American-Standard Eyepiece Sleeve and Built-In Adapter-Mounting Screw
The XW series features the American-standard 50.8mm (2") barrel for smooth, easy installation on telescopes. When the rotatable eyecup is removed, it also offers an adapter-mounting screw/thread (48mm in diameter with a 0.75mm pitch).
| Free Shipping Graphic | Free US Shipping |
|---|---|
| Eyepiece Series | XW |
| Focal Length | 40mm |
| Barrel Size | 2" (50.8mm) |
| Apparent Field of View (Mfg Specified) | 70° |
| Eye Relief (Designed) | 20mm |
| Filter Threads | Standard 2" Filter Thread (M48 x 0.75) |
| Coatings | Fully Multicoated |
| Lens Elements | 6 |
| Lens Groups | 5 |
| Barrel Type | With safety undercut |
| Protective Plastic Storage Container | Yes - Manufacturer Supplied |
| Height (With Eyeguard Extended) | 117mm / 4.61" |
| Maximum Width | 76mm / 2.99" |
| End Caps | 2 |
| Rubber Eye Guard | Yes |
| Weight | 26.1 oz / 740 g |
| Country of Manufacture | Japan |
| Misc. Information |
Water proof: Yes (JIS Class 4) Weather protection: Yes |
| Hide Found a better Shipped Price on Frontend? | No |
Pentax 2" SMC XW40-R Eyepiece - 40mm # 70538