Corvane Gannet 127 catadioptric, tube with equatorial mount

Specifications

Description

The Gannet 127 is a Schmidt-Cassegrain catadioptric telescope with 127 mm of aperture and 1270 mm of focal length, giving an f/10 focal ratio. Light enters through a thin corrector plate, reflects from a spherical primary mirror to a secondary mirror mounted on the plate, and passes back through a hole in the primary to the eyepiece. This folded path packs a long focal length into a compact tube.

At f/10 the Gannet 127 gives high magnification on the Moon, the planets, and close double stars, while a 25 mm eyepiece still yields a field wide enough to frame larger planetary nebulae. The corrector plate and secondary mirror produce a central obstruction, so planetary detail shows slightly less contrast than it would in an unobstructed reflector of the same aperture. The tube is baffled and the optics are coated to keep contrast steady on lunar work. Expect the thick corrector plate to take time to reach outdoor temperature, so set the telescope out before your session begins.

The focuser is a 1.25 in rack-and-pinion unit, and it accepts a star diagonal for overhead viewing. The 6x30 right-angle finder gives a wide field for star hopping before you switch to the eyepiece. At 6.2 kg for the tube, the Gannet 127 needs a sturdy equatorial or alt-az mount with a payload rating of at least 8 kg, so check the mount's load rating before you buy. Under dark skies, typical targets include the craters along the lunar terminator, the rings of Saturn, the cloud bands of Jupiter, and bright planetary nebulae such as the Ring Nebula in Lyra.

About this configuration

The Corvane Gannet 127 catadioptric is offered in several configurations, and the notes below describe what this particular combination adds or changes. The equatorial mount follows the sky along one axis once you align its polar axis with the celestial pole. With the equatorial mount, slow-motion controls let you keep a planet centered at high magnification with one hand. Matte black paint gives the telescope a low-key look, although a dark tube is harder to find on a moonless night.

Color filters from the planetary kit can bring out surface markings on Mars and the cloud belts of Jupiter. This is the 2025 edition, which updated the knobs and clamps so you can operate them with gloves on cold nights. Check the specifications table for the optical figures, since they stay the same across every configuration of the Gannet line.

What's in the box

• Optical tube with corrector plate
• Tube rings with dovetail bar
• 1.25 in star diagonal
• 6x30 right-angle finder
• Front and rear dust caps
• Equatorial mount with steel tripod
• Counterweight and counterweight shaft
• 6 mm planetary eyepiece (1.25 in)
• Four color filters (1.25 in)

Compatibility notes

• Accepts 1.25 in eyepieces through the rear focuser and the supplied diagonal.
• The included dovetail bar fits standard small and medium mounts.
• 2 in eyepieces require an optional reducer and are not supplied.