Vixen NPL Plössl 25mm eyepiece 50° 1.25″
The Vixen NPL Plössl 25mm is one of the most popular eyepieces in the NPL series - a line that has earned a solid reputation for combining genuine optical quality with an accessible price point. The 25mm focal length hits a comfortable middle ground: it delivers moderate magnification that works equally well for sweeping deep-sky objects and for observing the Moon and planets in a wide, well-framed view.
Optical design and coatings
The eyepiece is built on a classic 4-element Plössl design, which is well proven for delivering sharp, high-contrast images across the entire field. All optical surfaces are treated with FMC (Fully Multi-Coated) anti-reflection coatings, which maximise light transmission and suppress internal reflections and ghosting. The result is a bright, crisp image that holds up well even under moderately light-polluted skies.
The apparent field of view of 50° is typical for the Plössl class and provides a geometrically correct, undistorted image right to the edges - without the "fishbowl" effect found in some wide-angle designs.
Compatibility and practical features
The standard 1.25″ barrel fits every telescope with a standard focuser of that size, which covers the vast majority of refractors, reflectors and catadioptric telescopes on the market. The barrel is threaded for standard 1.25″ filters, so you can attach a Moon filter, a colour filter, or a UHC nebula filter directly - no adapters needed.
The compact size and low weight make this eyepiece a practical choice for binocular viewers, where having a matched pair of identical eyepieces is important for a balanced, comfortable experience.
Who is this eyepiece for?
The Vixen NPL Plössl 25mm is a reliable all-rounder that suits a wide range of observers:
- Beginners building their first eyepiece collection
- Intermediate observers who want a dependable wide-field eyepiece for star-hopping and deep-sky work
- Visual observers who use binocular viewers and need a matched pair
- Anyone looking for a budget-friendly eyepiece that does not sacrifice optical quality
Specifications
| Parameter |
Value |
| Focal length |
25 mm |
| Optical design |
Plössl (4 elements in 2 groups) |
| Apparent field of view |
50° |
| Barrel diameter |
1.25″ |
| Coatings |
FMC - Fully Multi-Coated |
| Filter thread |
Yes - standard 1.25″ |
| Eye relief |
approx. 20 mm |
| Field stop diameter |
approx. 21.8 mm |
| Series |
Vixen NPL |
Choosing the right focal length
A 25mm eyepiece is considered a classic starting point in any eyepiece kit. In a typical short refractor (f/5-f/6), it delivers around 20-30x magnification - ideal for large nebulae and open clusters. In a longer instrument (f/8-f/10), magnification rises to 40-60x, which works well for globular clusters, galaxies, and general lunar observation. This makes the NPL 25mm a genuinely versatile choice regardless of the telescope you use it with.
The Vixen NPL series
The NPL line is Vixen's entry-level eyepiece range, designed to offer reliable performance at a reasonable price. All eyepieces in the series share the same 1.25″ barrel, FMC coatings, and filter thread, making it easy to build a consistent set. The range covers focal lengths from 6mm to 40mm, so you can expand your kit gradually without switching between incompatible systems.
