Test Driving Svbony’s Entry-Level Telescope: the SV520 90mm f/8.9 Refractor.

A Work Commenced April 14 2025

When it comes to introducing the wonders of the night sky to beginners, it’s very hard  to beat a small refractor. Praised for their crisp, high-contrast views and almost complete lack of maintenance, even absolute newcomers can quickly engage with the night sky. Over the last few years, the newly established company, Svbony, has brought to market very high quality astronomical gear at prices that were considered unthinkable only a few years ago. As a seasoned amateur astronomer, and experienced reviewer of telescopes, I have used Svbony eyepieces and other accessories with my own telescopes and can vouch for their great bang for buck.

Svbony reached out to me to request an honest review of their new entry-level telescope; the SV520 telescope: a 90mm air spaced F/8.9 achromatic refractor on a dedicated altazimuth mount with slow motion controls on both axes.  I agreed to do so, and what follows is a fairly detailed overview of its quality and capabilities.

The SV520 telescope, mount and accessories arrived in a well packed double box. Though the instruction manual is clear and comprehensive, I found it easy to assemble the mount and attach the telescope in just a few minutes. 

Let’s take a closer look at the telescope mount first. Having used a Vixen Porta II altazimuth mount for nearly 15 years, I was delighted to see that the SV520 came with a very similarly designed unit. It can accept a wide range of small telescopes using a regular dovetail plate. Slow motion controls provide smooth and precise tracking on both axes. The legs of the tripod seem to be made of stainless steel and can be extended to increase the overall height of the telescope for taller users. The legs can be securely locked in place using three large thumbscrews. The accessory tray screws onto the long vertical bar that mates the mount to the tripod legs. 

The set up is quite stable with the telescope mounted. After giving it a hefty shake, I found the dampening times to last for just a few seconds, which is more than adequate even when using high power eyepieces. Incidentally the mount can accommodate loads of up to 5 kilos.

Two eyepieces are provided with the optical rube assembly: a 25mm and 10mm Kelner delivering powers of 32x and  80x, respectively. A decent mirror diagonal is also included for comfortable 90 degree viewing. It is not threaded to accept filters though.

The finder was arguably the biggest disappointment in the SV 520 package: a very plasticky 5 x 24mm specification with a singlet objective lens. As you can imagine, it produces very strong colour fringing owing to its short and stubby focal length. But I was able to align it easily with the main telescope and it did serve its purposes as a basic finder scope. Indeed as bad as it is, I think it’s still infinitely better than a generic red dot finder all too often seen on amateur scopes these days. 

The SV520 comes with a removable plastic dew shield, which reveals the lens cell underneath. The focuser is a single-speed rack and pinion design, which moves very smoothly and has enough focus travel to use quite a lot of accessories including diagonals, or mounting photographic gear. It can also be rigidly locked in place if need be.

Optical Testing


To be Continued……..

De Fideli.

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