Corvane Sedge 20x40 binoculars
20x magnification · 40 mm objectives · 2.5° field
$139
Catalog preview. Not available for purchase.
- Package
- Binoculars only
- Optics
- Fully multi-coated optics
- Armor
- Slate gray armor
- Edition
- 2023 edition
Specifications
| Magnification | 20x |
|---|---|
| Objective diameter | 40 mm |
| True field of view | 2.5° |
| Exit pupil | 2.0 mm |
| Dawes limit | 2.90 arcsec |
| Limiting magnitude | 10.0 |
| Eye relief | 14 mm |
| Close focus | 10.0 m |
| Prisms | BaK-4 Porro |
| Weather sealing | Not sealed |
| Weight | 1,100 g |
| Package | Binoculars only |
| Optics | Fully multi-coated optics |
| Armor | Slate gray armor |
| Edition | 2023 edition |
Description
The Sedge 20x40 is a Porro-prism binocular with 40 mm objectives and 20x magnification. The exit pupil is 2 mm, which keeps the image bright enough for the Moon, bright planets, and double stars. At 20x the true field is 2.5 degrees, about five times the diameter of the full Moon, so you see a small part of the sky at a time.
Magnification this high shows every hand tremor, so use a tripod with a standard binocular adapter, or rest the binoculars on a fence post or car roof. Scan the Orion Nebula, the Double Cluster in Perseus, and the Beehive Cluster in Cancer. Near first quarter, follow the terminator, where crater rims cast long shadows. The narrow field makes objects slower to find, so start with a bright star you can identify, then move the binoculars in small steps.
The BaK-4 Porro prisms and the central focus wheel adjust quickly. The binoculars are not sealed, so keep them out of dew and store them in the soft case when the optics are damp. The 14 mm eye relief suits observers who remove their glasses. Observers who wear glasses may see a reduced field edge, so check the view with glasses on before a session.
At 1100 g, the Sedge 20x40 is heavy to hold for long periods. Use a tripod or a binocular harness, and set the right-eye diopter on a bright star before you focus with the central wheel. The 10 m close focus also allows viewing nearby terrestrial subjects.
About this configuration
The Corvane Sedge 20x40 binoculars comes in several configurations, and the notes below explain what this particular combination includes. This package contains the binoculars with their strap, lens caps, and case, without any mounting hardware. If you later want steadier views, the tripod socket between the barrels accepts a standard L-shaped adapter. Fully multi-coated optics treat every air-to-glass surface, which raises light transmission and image contrast.
Slate gray armor uses a slightly harder rubber compound that resists scuffs from tripod clamps and cases. 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
- 1/4-20 tripod adapter
Compatibility notes
- The central tripod socket takes a standard L-shaped binocular adapter with a 1/4-20 thread.
- Fits binocular harnesses rated for 1.2 kg.