Northmere Tundra 20x70 ED binoculars, with parallelogram mount

Specifications

Description

The Tundra 20x70 ED binoculars pair 70 mm objectives with 20x magnification. The exit pupil measures 3.5 mm, which keeps the image bright under dark skies, and the true field of 2.8 degrees gives an apparent field of about 56 degrees. Targets such as the Orion Nebula, the Double Cluster in Perseus, and the Wild Duck Cluster in Scutum show detail that smaller binoculars do not resolve.

Extra-low-dispersion glass reduces color fringing around bright stars such as Vega and Capella, so the field edges stay sharper at high magnification. The 20x power shows the dense star fields of the Milky Way in Cygnus and Sagittarius more clearly than wider glasses, and star counts across the Cygnus Star Cloud reward a slow sweep. Use a smooth pan along a single star path, and note how many stars enter and leave the view in one minute.

At 2,850 g, these binoculars need a stable support. Mount them on the central tripod socket with a rated adapter and a fixed tripod, or use a parallelogram harness rated for at least 3 kg. Balance the binoculars before you start, so the wrists and neck stay relaxed during long sessions. The 9.0 m close focus allows you to check focus on a nearby landmark before the sky is fully dark.

The 15 mm eye relief suits observers who wear glasses, though the full field is most easily seen with the eyecups extended. For a first session, start with the Double Cluster in Perseus, then move to the Andromeda Galaxy and compare the star counts along the edges of each view. Record the position of each target against the nearest bright star to build a reference for later nights.

About this configuration

All configurations of the Northmere Tundra 20x70 ED binoculars share the same magnification and objective size; the options below change the package and finish. The parallelogram mount keeps the binoculars at eye level while you move them across the sky in smooth arcs. A parallelogram mount lets observers of different heights share the same view without aiming the binoculars again. The ED version adds low-dispersion glass and full multi-coating for sharper star images toward the edge of the field.

The slate gray finish makes the binoculars easier to find on a dark table than the black armor does. The 2023 edition uses the same prisms and objectives as later years, with small differences in the eyecups. 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 neck strap
• Objective and rain guard caps
• Hard carrying case
• Lens cleaning cloth
• Parallelogram mount with counterweight
• Tripod adapter

Compatibility notes

• The central tripod socket takes a standard L-shaped binocular adapter with a 1/4-20 thread.
• Fits parallelogram harnesses and mounts rated for 3 kg binoculars.