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Most amateur astronomers, and even people with only a casual interest in stargazing, have heard of smart telescopes or “smartscopes”—small-aperture robotic telescopes that take pictures of celestial objects with little human intervention. Smartscope users view the astroimages they take on smart devices, phones or tablets; there is no eyepiece for visual observation.
Specifications
Aperture: 50 mm
Focal length: 250 mm
Focal length: f/5
Sensor: 2.1 megapixel Sony IMX462 CMOS sensor (color)
Resolution: 1920 x 1080 pixels
Battery: Lithium, rechargeable with USB-C charger
Battery capacity: 5 Ah
Battery life: 3.5 – 5 hours
Connection: Wi-fi (Bluetooth used in initial setup)
Weight: 5.51 lbs / 2.5 kg
ZWO SeeStar S50 review
ZWO SeeStar S50: Design
- A compact and lightweight package is ideal for travel
- Operates in either alt-azimuth or equatorial mode
- Everything is controlled via the accompanying app
The SeeStar S50 smartscope is an apochromatic (colorless) refractor with an aperture of 50 mm and a focal length of 250 mm. The heart of the S50 is the built-in camera, which features a Sony IMX462 2.1-megapixel, 1920 x 1080 color sensor that’s well suited to the SeeStar’s 0.73 x 1.3-degree field of view. There is 64 GB of internal memory for storing astro images. Like other smart scopes, the S50 takes several short exposures and stacks them into finished astrophotos.
The S50’s features include GoTo and tracking motors that can operate in either altazimuth or equatorial mode, and Wi-Fi and Bluetooth support. It has a built-in Light Pollution Reduction (LPR) filter for imaging from light-polluted locations. There’s even an internal mist heater to keep your optics clear on humid nights. All of this comes in a compact, lightweight package that weighs 2.5 kilograms and measures 5.6 x 5.1 x 10.1 inches (142.5 x 130 x 257 millimeters).
When a new owner opens the SeeStar box, the first item they encounter is a carrying case. Although it is made of a Styrofoam-like material, it holds up well. Inside is the black, plastic S50, which looks more like a coffee maker than a telescope. Also in the case is a carbon fiber table top. It only raises the telescope 355mm from the ground, but is usable. Finally, there is a USB charging cable, an impression solar filter and a short instruction leaflet.
Unlike conventional computerized telescopes, the S50 has no hand control. Everything is done from a phone or tablet, so the first step to getting it ready to take astrophotos is to download the free SeeStar app from the Google Play Store or Apple App Store. There is no PC version, but the app will run on newer Apple computers with M processors.
ZWO SeeStar S50: Performance
- The app has easy-to-follow instructions
- “Tonight’s Best” offers an easy way to find objects
- Bright objects like M42 are easy to see with short exposures
The S50 doesn’t need much in the way of a manual, because the app has step-by-step instructions and tutorials. Turn on the SeeStar by holding down the power button until the scope beeps twice, then release the button. When this speakerphone announces “Power on, ready to connect,” open the app and follow the instructions.
The SeeStar app offers several ways to select targets, including selecting from a list of the evening’s best. An easy way to find other objects is by using the built-in and comprehensive star atlas, accessed by tapping the SkyAtlas icon at the bottom of the home screen. To image the Orion Nebula, M42, for example, select “Object” and enter “M42” in the atlas search field.
After the nebula is on the atlas screen, send SeeStar to M42 by pressing “go-to”. When the telescope arrives at its destination, it takes pictures of the star field and compares them to maps in memory (“plate resolution”) to make sure it’s in the right place. It is quite accurate.
Then the app switches to a “live” camera view and autofocus. A bright object like M42 is easy to see in the short exposures. After the telescope has focused, press the red “shutter” button at the bottom of the screen, it will begin taking 10-second exposures (default). The target object will begin to “evolve” as exposures are added together.
In less than a minute, SeeStar can produce a color image of the Orion Nebula that shows far more detail than can be seen visually in large telescopes.
ZWO SeeStar S50: Functionality
- Connection via Bluetooth and WiFi
- The app can feel overwhelming at first, but you’ll soon learn the ropes
- Can be connected to your home network
The first time the S50 is used, it must be connected to your smart device using Bluetooth. When Bluetooth is activated, the scope connects directly to your phone or tablet via Wi-Fi. The next time SeeStar is used, Bluetooth will not be needed.
At first, the SeeStar app seems overwhelming, with many choices and options in unintuitive places. But with a little experience, the process of taking astrophotos becomes easier. It would help if ZWO didn’t keep changing the app to the point where it has to be relearned frequently. However, the telescope’s outstanding images are worth some training. The SeeStar itself is remarkably trouble-free for such a relatively inexpensive instrument.
This direct Wi-Fi connection works well and is convenient for use in dark places. At home, however, it is best to use “Station mode”. It allows the telescope to be connected to a home network instead of directly to a phone or tablet. In station mode, your smart device can be used as normal and does not need to be near the scope.
Should you buy the ZWO SeeStar S50?
Is ZWO’s SeeStar S50 perfect? Of course not, no telescope is; there are some problems. The most important is that ZWO updates the SeeStar app every so often. While adding new features is great, bugs – sometimes serious ones – are also introduced.
The SeeStar produces impressive out-of-the-box results in altazimuth mode, but 10-second exposures (the scope can expose for as long as 60 seconds) are practically mandatory. Going to 20 seconds, which produces less noisy images, results in dropped frames and trailing stars. However, there is a solution: equatorial or “EQ” mode.
In EQ mode, the SeeStar is tilted so that the body points roughly towards the north (or south) celestial pole. The app includes a built-in routine that allows the S50 to be accurately polar aligned. However, using EQ mode requires the purchase of additional equipment: either a full-sized camera tripod with a tilting head, or one of the equatorial wedges sold for SeeStar. Under most conditions, EQ mode produces markedly superior images.
Who is SeeStar specifically? not to? Those who are most interested in the moon and planets. Although it can produce nice solid-disk images of the Sun (with the included solar filter) and Moon, planets will look very small with only the 250mm telescope focal length.
If this product is not for you
If you’d rather see the cosmos with your own eyes than on a screen, you can’t go wrong with the beloved Celestron NexStar 8SE – known as the world’s most beloved telescope.
Read all spring Celestron NexStar 8SE review
If you’d rather invest more in one of the most affordable telescopes you can buy, we’d recommend the Vaonis Vespera II. The pictures are amazing and it’s a very reasonable price compared to some of the competition.
Read all spring Vaonis Vespera II review
Sky-Watcher SkyMax 180 Pro
Smart telescopes are usually designed for deep sky objects, so you’ll want an observing telescope with a good aperture to resolve details in the planets – something like the Sky-Watcher SkyMax 180 Pro.
