Pentax XW 7mm 70° 1.25″ Eyepiece
The Pentax XW 7mm eyepiece combines a short focal length with a 70° apparent field of view. This makes it far more comfortable to use than traditional narrow-field designs when observing planets, the Moon, or globular clusters. Low-dispersion lanthanum glass delivers high resolution and keeps chromatic aberration and distortion to a minimum - the image stays sharp and accurate right to the edge of the field of view.
Optical design and coating
The optical design was developed using extensive computer simulation. The result is a significant reduction in internal reflections and a noticeable improvement in overall image brightness. All optical elements carry the Pentax SMC multi-layer coating - one of the finest anti-reflection coatings available in astronomical optics today.
The hybrid optical system uses eight lenses in six groups. The 20mm eye relief makes this eyepiece comfortable for eyeglass wearers as well.
Durability and camera compatibility
The XW series meets the JIS Class 4 waterproof standard. This means the eyepiece handles rainy nights and high-humidity conditions without any issues.
The Pentax XW 7mm eyepiece matches the build quality and optical performance of leading brands such as Tele Vue. The M43x0.75 thread allows direct camera attachment for astrophotography.
Key features at a glance
- 70° apparent field of view - wide and immersive view
- Low-dispersion lanthanum glass for sharp, high-contrast images
- Pentax SMC multi-layer coating on all optical elements
- Eight lenses in six groups - hybrid optical design
- 20mm eye relief - suitable for eyeglass wearers
- JIS Class 4 waterproof rating - reliable in all weather
- M43x0.75 thread for direct camera attachment
- 1.25″ barrel - fits all standard focusers
Technical specifications
| Parameter |
Value |
| Focal length |
7mm |
| Apparent field of view |
70° |
| Eye relief |
20mm |
| Optical design |
8 lenses in 6 groups |
| Coating |
Pentax SMC (fully multi-coated) |
| Glass type |
Low-dispersion lanthanum glass |
| Barrel size |
1.25″ |
| Camera thread |
M43x0.75 |
| Waterproof rating |
JIS Class 4 |
Who is this eyepiece for?
The Pentax XW 7mm is an excellent choice for observers who want a wide, sharp view at high magnification. It works particularly well for planetary detail, lunar observation, and globular clusters. The wide field of view and generous eye relief make long observing sessions genuinely enjoyable - with or without glasses.
If you are looking for a premium 1.25″ eyepiece that delivers consistent optical quality at the edge of what is available today, the Pentax XW 7mm is a serious option worth considering.
