Celestron StarSense Explorer DX 130AZ Telescope Review

The DX 130AZ is a 5.1-inch Newtonian reflector with a focal length of 650mm and a focal ratio of f/5. Credit: Celestron

Who wants a manual telescope these days? With Go-To all the rage for the last decade or so the appearance of a completely manual Newtonian reflector telescope claiming to be the latest in technological advances is something of a surprise. However, the DX 130AZ has something that few other telescopes have—a smartphone mount.

The idea is pretty simple, if rather ingenious. You download Celstron’s free StarSense Explorer to any smartphone, place the device in the mount’s universal clamp and lift-up a flap to reveal a small mirror directly below your smartphone’s camera. It then aligns the stars your phone’s camera sees in reflection with its own database. It’s a technique called plate-solving. 

The tripod supplied is just about stable enough. Credit: Celestron

Magic?! Well, not quite. It does work, but not always. First, you need to align your smartphone so its camera is over the mirror, with left-right and up-down knobs on the smartphone adapter helping out here. Under a dark and moonless sky, the app quickly sorts out where it is, but used around a First Quarter moon it struggles. Strong light pollution can put it off course, too. That’s perhaps not surprising, but it is a little disappointing. 

The StarSense Explorer app is best used in color mode. Credit: Jamie Carter

Under dark skies, however, it’s impressive. Pick a target and it will walk you to it using a combination of arrows and bullseye targets. The StarSense Explorer app is based on the hand controllers provided with Go-To telescopes for many years. There’s the familiar “tonight’s best” lists, the same extensive database of (and exhaustive information on) celestial objects, and the same spoken-word feature for when you want hands-free commentary on what you’re studying. However, since it’s all now on an app instead of coming through a speaker on a handset, you can also attach a pair of wireless Bluetooth earphones.

As well as arrows and bullseyes the StarSense Explorer app contains descriptions and spoken-word audio. Credit: Jamie Carter

Happily, these convenient features are matched by impressive optics for the money. A 5.1-inch Newtonian reflector with a focal length of 650mm and a focal ratio of f/5, the DX 130AZ ships with a couple of rather low-power and basic 25mm (26x) and 10mm (65x) 1.25-inch eyepieces. They provide sharp enough views for beginners. Time spent object-hopping around the Big Dipper afforded precise views of Mizar and Alcor as well as the Cigar Galaxy (M82) and Bode’s Galaxy (M81), though the Cat’s Eye Nebula (NGC 6543) was merely star-like at such low-power. The Moon’s surface looked sharp through the 25mm eyepiece, with shadows thrown across the southern highlands impressing.

The dual controls for focus are smooth and ridged for use with gloves. Credit: Celestron

Something I wasn’t impressed much by was the tripod. A black aluminum affair that’s easy enough to set-up, it lacks solidity for such a large telescope. That’s especially troublesome since the DX 130AZ is a manual telescope (it also includes a red dot finder), so positioning it causes constant vibrations. The soft-touch dual-axis slow-motion controls do help make fine adjustments, but even they’re not hands-free.

The app’s red light mode does make it more difficult to use. Credit: Jamie Carter

One thing to remember when using the StarSense Explorer app is that you have to take care of your smartphone. First, turn the brightness down. Nobody needs bright, white light ruining their night vision! Second, engage the built-in red light mode … though only after you’ve moved on from needing to know when the various on-screen arrows and bullseyes are red, yellow, and green. Thirdly, place a portable smartphone battery on the tripod’s spreader tray and connect it to your smartphone while it’s in the mount (there’s a cut-out to make space for this, which is a nice design detail).

Dual-axis fine controls are used for making slight adjustments. Credit: Celestron

The DX 130AZ is well designed, albeit partly to make it more affordable, but I can’t help feeling there’s a missed opportunity here for some kind of astrophotography option. Of course, you can easily indulge in a little basic afocal astrophotography by simply putting your smartphone camera to the eyepiece. However, the smartphone cradle itself is hugely reminiscent of the Celestron NexGO smartphone adapter, which is designed to clamp around an eyepiece for more accurate afocal astrophotography. Couldn’t the smartphone holder on the DX 130AZ somehow be detached to morph into a NexGo?

The smartphone holder is reminiscent of Celestron NexGo smartphone adaptors for afocal astrophotography. Credit: Jamie Carter

A few small issues aside, the DX 130AZ does seem good value for money and it’s always easy to use. Its manual design means beginners get the ease of smartphone app guidance, but also an education in how to navigate the night sky. That’s more than you can say about Go-To telescopes.’

The spreader tray is just solid enough to use for eyepieces. Credit: Celestron


Plus: Sharp optics; easy to use app; manual operation helps beginners learn to navigate the night sky

Minus: StarSense is affected by strong moonlight; average-quality eyepieces; average tripod


MSRP: $449


About Jamie Carter

A science, travel and technology journalist for over 20 years, UK-based Jamie Carter writes for Forbes Science, Sky and Telescope magazine, the BBC's Sky At Night, Travel+Leisure and the South China Morning Post. He edits, leads tours to see eclipses, and regularly tweets about stargazing (@jamieacarter) and eclipses (@thenexteclipse).

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