Northmere Tundra 15x100 ED binoculars

Specifications

Description

The Tundra 15x100 ED binoculars pair 100 mm objectives with 15x magnification, which gives an exit pupil of about 6.7 mm. The large aperture gathers enough light to show faint star clusters and bright nebulae under dark skies, and the exit pupil suits observers whose dark-adapted pupils open wide. Extra-low-dispersion glass in the objectives reduces color fringing around bright stars and the lunar limb.

A true field of 4.0 degrees gives an apparent field of about 60 degrees. Star fields in Cygnus, Sagittarius, and Scorpius fill the view, and the Pleiades, the Double Cluster in Perseus, and the Orion Nebula fit within the field with room to spare. At 4.2 kg, the binoculars are too heavy for steady hand-held use at 15x, so mount them on a tripod with a rotating adapter that keeps the eyepieces level as you change altitude. The 20 mm eye relief lets you keep your glasses on and still see the full field, and the 10 m close focus lets you view nearby ground objects.

The body is nitrogen-purged and waterproof, so the optics resist fogging and remain usable in damp conditions and during dew formation. The central focus wheel moves through a long travel for precise focus at this magnification, and the right-eye diopter corrects for differences between your eyes. To check alignment, center a bright star and switch between eyes; the star should stay centered in both views.

Use a tripod with a payload rating well above 4.2 kg, and set it on firm ground to limit vibration. Start with the Moon to test focus and sharpness, then sweep along the Milky Way from Cygnus toward Cassiopeia. Note which clusters and nebulae you can resolve, and return to them on a darker night to compare the difference that sky transparency makes.

About this configuration

This listing covers one configuration of the Northmere Tundra 15x100 ED binoculars, defined by its package, optical coatings, armor color, and edition year. This package contains the binoculars with their strap, lens caps, and case, without any mounting hardware. Binoculars alone suit hand-held scanning of the Milky Way, bright star clusters, and the phases of the Moon. The ED version adds low-dispersion glass and full multi-coating for sharper star images toward the edge of the field.

The olive armor has the same grip pattern and thickness as the other colors in the Tundra line. This is the 2023 edition of the Tundra line, the earliest version that is still listed in the catalog. Compare the exit pupil in the specifications with your sky conditions and your age, since both affect how bright the view looks.

What's in the box

• Binoculars with center-post tripod adapter
• Objective and eyepiece rain caps
• Padded carrying case
• Neck strap
• Lens cleaning cloth

Compatibility notes

• The central tripod socket takes a standard 1/4-20 adapter with a rotating L-bracket.
• Requires a mount with a payload rating of at least 6 kg, such as a heavy-duty fork or parallelogram mount.