Vixen NPL Plössl 40mm eyepiece 1.25″
The Vixen NPL series represents a well-established line of Plössl eyepieces that successfully combines an accessible price with solid optical performance. The classic four-element design (4 elements in 2 groups) with fully multi-coated (FMC) optics delivers excellent light transmission and high image contrast - qualities that make a real difference when observing extended deep-sky objects such as open star clusters, nebulae, and sweeping sections of the Milky Way.
With a focal length of 40mm and a 40° apparent field of view, this eyepiece is an ideal choice for low-magnification, wide-field observing sessions. It gives a true overview of large sky areas and works equally well for initial object location and leisurely star-hopping across the night sky.
Key features
- Plössl design - 4 elements in 2 groups
- Fully multi-coated (FMC) optics for high light throughput and contrast
- Focal length: 40mm
- Apparent field of view: 40°
- Barrel diameter: 1.25″
- Standard 1.25″ filter thread for easy use with Moon filters, UHC, OIII or other astronomy filters
- Compact and lightweight - well suited for binoviewers where load balance matters
Technical specifications
| Parameter |
Value |
| Optical design |
Plössl (4 elements / 2 groups) |
| Focal length |
40mm |
| Apparent field of view |
40° |
| Barrel diameter |
1.25″ |
| Filter thread |
1.25″ standard |
| Lens coatings |
FMC (fully multi-coated) |
| Eye relief |
approx. 25mm |
Who is this eyepiece for?
The Vixen NPL 40mm suits a wide range of observers. Beginners will appreciate it as a first high-quality wide-field eyepiece that pairs well with almost any telescope. Experienced observers will find it a reliable low-power overview eyepiece to complement a more complete eyepiece collection - useful for scanning large nebulae, locating objects before switching to higher magnification, or simply enjoying panoramic views of rich star fields.
Its compact dimensions and low weight make it one of the most practical choices for use in binocular viewers (binoviewers), where a matching pair of lightweight eyepieces is essential for comfortable, balanced viewing.
Recommended observing targets
- Open star clusters - Pleiades, Hyades, Beehive Cluster
- Large nebulae - Orion Nebula, Lagoon Nebula, North America Nebula
- Milky Way sweeping and star-field browsing
- Wide double stars and asterisms
- Initial location of deep-sky objects before switching to higher magnification
Filter compatibility
The 1.25″ barrel includes a standard filter thread, allowing you to attach a broad range of astronomy filters directly to the eyepiece. A Moon filter reduces glare during lunar observations, while UHC or OIII narrowband filters enhance the contrast of emission nebulae and planetary nebulae under light-polluted skies.
About the Vixen NPL series
The NPL line from the Japanese manufacturer Vixen has long been recognised as a dependable entry point into quality astronomical eyepieces. Built to consistent optical and mechanical standards, NPL eyepieces offer a straightforward and honest performance that holds up well against much more expensive alternatives - making them a popular choice in both beginner telescope kits and experienced observers' eyepiece cases.
