Halden Corvid 130 APO triplet refractor, tube only

Specifications

Description

The Corvid 130 is an air-spaced triplet refractor with 130 mm of aperture and 910 mm of focal length, for a focal ratio of f/7. Its three lens elements include one of low-dispersion glass, which brings red, green, and blue light to a common focus closely enough that bright stars show no visible color fringe at the eyepiece.

That color correction makes the Corvid 130 suitable for both high-power visual work and imaging. On a steady night it can split close double stars near its resolution limit, show festoons in the equatorial belts of Jupiter, and hold a crisp image of lunar craters at magnifications above 200x. With a camera, stars stay round and tight in the center of the field; a field flattener extends that across a larger sensor.

The 3 in rack-and-pinion focuser has a rotator and a lock, so a camera and filter wheel stay where you set them through a full night. The focuser drawtube has a scale for repeating the focus position. A sliding dew shield extends well past the objective and retracts for transport.

The tube weighs 7.8 kg, so it needs a mount rated for at least 12 kg once you add a diagonal, a finder, and an eyepiece, or a camera and guide scope. The supplied D-style dovetail suits medium equatorial mounts. Allow about 30 to 45 minutes for the thick lens to settle to the outdoor temperature on a cold night.

For deep-sky observing, the 130 mm aperture shows the spiral arms of M51 under dark skies and resolves the outer stars of bright globular clusters such as M13. Wide-field views of the Pleiades or the Double Cluster fit easily with a 2 in eyepiece.

About this configuration

The Halden Corvid 130 APO triplet refractor is offered in several configurations, and the notes below describe what this particular combination adds or changes. Buying the tube alone makes sense if you already own a suitable mount or plan to choose one separately. Without a mount in the package, check the tube weight against the payload rating of your mount, with some margin to spare. The carbon fiber tube expands less as the temperature drops, so the focus point drifts less as the night cools.

This configuration comes without extra accessories, so budget for at least one more eyepiece if you are starting out. The optics in the 2024 edition match the other years; the changes concern hardware details only. The optical figures in the specifications table apply to this configuration and to every other version of the Halden Corvid 130 APO triplet refractor.

What's in the box

• Optical tube with sliding dew shield
• Hinged tube rings with D-style dovetail bar
• Carry handle with finder shoe
• 2 in diagonal with 1.25 in adapter
• Fitted hard case

Compatibility notes

• Needs an equatorial or alt-az mount rated for at least 12 kg with accessories.
• The D-style dovetail fits mounts with a D-style or dual saddle.
• The 3 in focuser accepts 2 in and 1.25 in accessories through the supplied adapters.
• A field flattener with 55 mm back focus suits full-frame and APS-C cameras.