Sky-Watcher SupaTrak auto-tracking mount & OTAs
Optical Vision Ltd. — +44 (0)1359 244200 — from £199 SRP
Written: ~5 years ago

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If you read my piece on the Orion TeleTrack in Astronomy Now's February 2007 issue, or saw my online précis here, you'll know that motorised altazimuth mounts are becoming increasingly popular. It's not surprising, then, that the TeleTrack's developer — Taiwanese optical giant Synta — should employ the same technology in something rather more suited to larger astronomical/terrestrial telescopes.

Launched under the Sky-Watcher brand, the new SupaTrak mount shares more than a passing resemblance to the Celestron SLT, but the somewhat quieter and heavier duty SupaTrak sports a more robust Vixen-style dovetail clamp. Unlike the SLT, however, the SupaTrak dispenses with internal AA batteries in favour of an exclusively external 12V DC power source and the computerised hand controller is exchanged for a far simpler nine-button version.

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So, how does it work? The modus operandi is essentially identical to that of the TeleTrack. A simple one-time setup procedure requires you to establish your latitude by setting an index mark against a built-in degree scale on the altitude axis. Pressing the Slow (2) and Fast (3) buttons together saves this setting which is remembered between sessions. So provided that you don't travel too far, power up with the telescope tube level and facing north (a compass is provided) with the azimuth axis vertical, you're ready to track on demand by pressing the Guide (1) and Slow (2) buttons simultaneously.

This method of initialising and aligning an auto-tracking mount may not have the refinement of the 2- to 3-star alignments commonly encountered with GoTo mounts, but it's far faster and more inviting for the technophobe to perform. I found that the SupaTrak was capable of following a celestial object at high magnifications for tens of minutes before slowly drifting out of the field of view, which is perfectly adequate for visual use or simple webcam imaging. At low powers the mount will track an object for up to an hour or more. As for high-speed slewing, I found that the SupaTrak could traverse 90° in close to 30 seconds.

The SupaTrak is initially offered with one of two proven 5-inch optical tube assemblies:

Explorer-130P + SupaTrak (SRP £199)
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Until comparatively recently there existed an aperture void between the 4.5- and 6-inch Newtonian, one admirably filled by the well-figured 130mm (5.1-inch) f/5 parabolic mirror of the Sky-Watcher Explorer-130P. Its sharp optics and relatively small central obstruction (35mm = 27%) ensure that it delivers bright, diffraction-limited images for its aperture. The easily managed tube and 650mm focal length means that can view a true field of in excess of 2° with 1.25-inch format eyepieces, while well-corrected shorter focal length oculars will give you memorable views of the Moon and bright planets. In short, it’s a great all-rounder in its class. The 'scope comes with 10mm & 25mm eyepieces, 2x Barlow lens, red dot finder and compass.

Mounted via an integral Vixen-style dovetail bar on the SupaTrak, the average eyepiece height of the Explorer-130P with the tripod legs retracted is around 110cm; with the legs extended it's nearer 160cm. In the latter configuration vibration damping time on grass is in the region of three seconds. Be aware that the Explorer-130P does touch the mount at altitudes greater than 85°, so there is a small exclusion zone near the zenith with this instrument (no such restriction applies to the Skymax-127 model below).

Skymax-127 + SupaTrak (SRP £ 299)
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At just 33cm long and 14cm in diameter, the 127mm aperture f/12 Skymax-127 still packs a performance punch with a relatively short cool-down time for a 'scope of this type. The largest Maksutov-Cassegrain in the standard range (only the 150mm and 180mm Pro Series instruments are larger), this is one of the jewels in the Sky-Watcher crown. It's large enough to produce richly detailed, high-contrast lunar and planetary images, yet doesn't overtax smaller mounts like the SupaTrak. The Skymax-127's standard Vixen dovetail rail also ensures its compatibility with a wide range of other mounts. The 'scope comes with 10mm & 25mm eyepieces, a 2x Deluxe Barlow lens, 6x30 finder, erect image star diagonal and compass.

One might not consider the Skymax-127 for daytime terrestrial use, but the instrument comes with an erect image diagonal and is quite capable of focusing down to 8 metres with minimal image shift. The bright and sharp 6x30 finder sensibly comes on a longer bracket offering plenty of clearance from the OTA. Its internal baffle diameter of just under 23mm means that the Skymax-127 is a strictly 1.25-inch format instrument. While it hardly excels as a wide-field 'scope, it can still deliver a crisp ¾° field with low power eyepieces.

As with all catadioptric 'scopes, I wished that the manufacturer bundled a dewshield with the Skymax-127. With the SupaTrak's tripod legs retracted the average eyepiece height is close to 75cm, extending to about 130cm at full height. Vibration time on grass at full tripod extension is around two seconds.

Conclusions
A slightly heavier-duty tripod with tubular steel legs would've been nicer, but despite appearances the aluminium one supplied is adequately stable as demonstrated by the short vibration times. For novice and expert alike, if you are looking for an intuitive and far less intimidating user experience than that offered by cheaper GoTo mounts, the SupaTrak is highly recommended as a versatile grab-and-go system, particularly with this well-matched pair of optical tube assemblies.