Tessaro Caldera EQ mount, head only

Specifications

Description

The Caldera is a German equatorial mount for refractors, Catadioptric telescopes, and small reflectors with a combined load up to 8 kg. Its right ascension axis sits on a cast-aluminum yoke, and its declination axis turns on a pair of sealed bearings. Set the counterweights until the tube stays put when you release the clamps. You point the mount by hand, then use the slow-motion cables to center objects in the eyepiece.

Polar alignment starts with the built-in polar scope, which lights a reticle you align with the celestial pole. Once the mount is aligned, the right ascension motor follows the sky at sidereal rate, so a planetary or lunar view stays centered for an hour or more at medium power. The motor runs from a 12 V DC supply, so you can connect a 12 V battery for field use. Check the drive rate against the sky after the first hour, since small polar errors show up as slow drift in declination.

The dovetail saddle is 50 mm wide and has a safety screw that holds the bar while you tighten the main clamp. The head weighs 5.4 kg and sits on a standard 3/8-16 base thread for photo tripods. The counterweight shaft accepts standard 1-inch bore weights. Keep the total load, including the diagonal, eyepiece, finder, and any camera, well below the 8 kg rating.

The Caldera has no GoTo system, so you find each target by star hopping from a finder or a star chart, then use the slow-motion cables to center it. It suits observing from a permanent pier or a sturdy tripod, where the polar alignment can be kept between sessions.

About this configuration

Each configuration of the Tessaro Caldera EQ mount uses the same mount head; the options change what it stands on and what ships with it. This configuration is the mount head alone, so you supply a tripod or a pier with a matching top plate. Buying the head only makes sense when you already own a sturdy tripod or a permanent pier in the garden. A padded case makes it easier to carry the mount head to a dark site without knocks to the axes.

The anodized red finish makes the clamps and knobs easier to find by touch and by red light. The 2023 edition uses the same gears and bearings as later years, with small differences in the clamps. For steady views, keep the total load of tube, finder, and camera below the rated payload with some margin to spare.

What's in the box

• German equatorial mount head with dovetail saddle
• Polar alignment scope
• Right ascension and declination slow-motion cables
• 12 V DC power cable
• Counterweight shaft
• Padded carrying case

Compatibility notes

• Accepts dovetail bars up to 50 mm wide.
• The 3/8-16 base thread fits most photo tripods.
• Suits refractors and Catadioptric telescopes with a total load up to about 8 kg.