Eyepiece TeleVue Nagler Type 5 31mm 82° 2″

TeleVue Nagler Type 5 31mm 82° 2″ eyepiece

Some eyepieces become legends while still in active use - and the TeleVue Nagler Type 5 31mm is exactly one of them. This eyepiece represents the peak of the Nagler series, which has been setting the standard for wide field visual astronomy since its introduction in 1980. If you are looking for an eyepiece that truly opens up the night sky and gives you an immersive experience when observing star clusters, nebulae and galaxies, the Nagler 31mm is the answer.

Optics and field of view

The TeleVue Nagler Type 5 31mm delivers an apparent field of view of 82°, which creates the feeling of looking directly into space with no frame around the image. The six-element UWA (Ultra Wide Angle) optical design ensures excellent correction of coma, astigmatism and other aberrations all the way to the edge of the field. Multi-layer anti-reflection coatings on all optical surfaces maximise light transmission and contrast - a quality you will especially appreciate when viewing faint deep sky objects under a dark sky.

The 2″ barrel (standard 2-inch fitting) lets you take full advantage of the optics at low magnifications. The Nagler 31mm works perfectly as an overview eyepiece for sweeping the Milky Way or searching for Messier objects.

Comfort and practical use

Eye relief and wearers of glasses

Eye relief of 19mm is a very comfortable value for an eyepiece with this wide a field. Observers who wear glasses will be pleased to know they can keep their glasses on without losing any of the field of view.

Filter compatibility

The eyepiece has a standard 2″ filter thread, so you can easily use UHC, OIII or CLS filters for observing emission nebulae - no adapters or workarounds needed.

Weight and balance

At 133mm in length and 998g in weight, this is a substantial eyepiece - fully in line with TeleVue's premium design philosophy. When mounting it on your telescope, we recommend checking the balance of the scope, especially if you are using a smaller mount.

Note: the eyepiece does not support parfocal function, but this is not relevant here - it is an independent optical unit with its own precisely defined exit point.

Ideal telescope pairings and observing targets

The Nagler 31mm works best on medium to long refractors and Newtonians with a focal length of 1000-2000mm, where it delivers comfortable low-power magnification with a very large true field of view. It is an excellent choice for:

• Large open star clusters - Perseus, Hyades, Pleiades
• Extended emission nebulae - Orion Nebula, Lagoon Nebula
• Wide views of galaxies in the Local Group
• General sweeping and object-finding sessions along the Milky Way

The eyepiece does not use inert gas filling, but this is not a concern with normal use - the optical elements are precisely seated and the eyepiece shows no condensation issues even with significant temperature changes.

About TeleVue and the Nagler series

TeleVue eyepieces are designed by Al Nagler - an experienced optical engineer and former NASA collaborator. Among astronomers worldwide, TeleVue is a synonym for the highest optical quality and careful American craftsmanship. Every Nagler series eyepiece goes through strict quality control, and over the decades the series has earned the firm trust of both professional and advanced amateur astronomers.

Buying a TeleVue eyepiece is an investment in a tool that will serve you reliably at the telescope for decades to come - regardless of how the rest of your equipment changes over time.

Technical specifications