Tessaro Bellwether alt-az mount, with steel pier

Specifications

Description

The Bellwether is a manual alt-azimuth mount for catadioptric telescopes and medium refractors, rated for payloads up to 12 kg. Its fork arms hold the tube on both sides of the head, so the telescope stays balanced as you move it. The mount turns in altitude, up and down, and in azimuth, side to side, so you aim it at the object you want to see and the head keeps the tube where you leave it.

Slow-motion rods on both axes allow fine corrections at high magnification, where a small hand movement shakes the image. Tension knobs set how freely each axis turns, so you can keep the head stiff for steady pointing or loosen it for quick sweeps across the sky. The 100 mm dovetail saddle accepts standard dovetail bars, and a safety screw holds the bar in place while you tighten the main clamp.

The head weighs 6.4 kg, so the Bellwether is best set on a sturdy tripod or pier. A telescope of about 150 mm aperture on a Maksutov or Schmidt-Cassegrain tube fits within the rated payload, but long tubes take longer to settle after you focus. As a rule, keep the total load, including a diagonal, eyepiece, and finder, well below the 12 kg rating.

The Bellwether has no motors and does not track the sky. Objects drift out of the field within a minute at high power, so you will need to nudge the tube by hand. The mount suits relaxed visual sessions at low and medium magnification, where a steady setup and simple controls matter more than automatic tracking.

About this configuration

Each configuration of the Tessaro Bellwether alt-az mount uses the same mount head; the options change what it stands on and what ships with it. The steel pier raises the mount and leaves more room under the telescope for long refractors and cameras. A pier lets the telescope swing past the meridian without the tube or the camera hitting the legs. No add-on is included, which suits observers who already carry their own cases, bars, and power supplies.

Titanium gray anodizing shows dust less than black and keeps a uniform look over the years. The 2023 edition uses the same gears and bearings as later years, with small differences in the clamps. The payload rating in the specifications applies to the mount head in every configuration of the Bellwether line.

What's in the box

• Alt-az fork mount head
• Two slow-motion control rods
• 100 mm dovetail saddle
• Accessory tray
• Steel pier with leveling base

Compatibility notes

• Accepts dovetail bars up to 100 mm wide.
• The 3/8-16 base thread fits most photo tripods; a 1/4-20 adapter is included.
• Suits telescopes up to about 150 mm aperture and 8 kg for steady views.