Quillon Tessera 15x38 binoculars

Specifications

Description

The Tessera 15x38 is a compact binocular with 38 mm objectives and 15x magnification. Its true field of 3.6 degrees gives an apparent field of about 54 degrees, and the 2.5 mm exit pupil makes the view bright on high-contrast targets such as the Moon, the planets, and bright double stars. Faint deep-sky objects look dimmer than through a 7x50 or 10x50 instrument, so the 15x38 suits detail more than wide sweeps.

Roof prisms of BaK-4 glass keep the optical path short, and the body weighs 780 g, which is manageable by hand for brief sessions but benefits from a monopod or a tripod adapter for steady viewing at this magnification. Fully multi-coated lenses reduce reflections on all air-glass surfaces. The 14 mm eye relief lets observers who wear glasses see the full field, and the rubber eyecups fold down when needed.

The body is nitrogen-purged and sealed with O-rings, so it resists fogging and light rain, though it is not rated for immersion. The central focus wheel turns with a smooth action, and the right-eye diopter corrects for a difference between your eyes. The close focus of 10 m lets you examine nearby objects, such as a bird on a branch, in daylight.

For a first session, start with the Moon a few days after new, then move along the terminator to see craters in relief. Next, sweep the Beehive cluster in Cancer and the Double Cluster in Perseus, and note how many stars each field holds. Return to the same fields on a darker night to compare the difference in star counts. Record the magnitude of the faintest star you can see in each field.

About this configuration

All configurations of the Quillon Tessera 15x38 binoculars share the same magnification and objective size; the options below change the package and finish. Binoculars alone suit hand-held scanning of the Milky Way, bright star clusters, and the phases of the Moon. If you later want steadier views, the tripod socket between the barrels accepts a standard L-shaped adapter. ED glass reduces the color fringing that otherwise appears around bright objects such as the Moon and Venus.

The tan armor is easy to spot when you set the binoculars down on the grass in the dark. 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 eyepiece caps
• Soft carrying case
• Lens cleaning cloth

Compatibility notes

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