ZWO SeeStar S50 smart telescope review
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Most amateur astronomers, and even those only interested in stargazing, have heard of intelligent telescopes or “smartscopes” – small-aperture robotic telescopes that take images of objects in the sky with little human intervention. Smartscope users view the astrophotos they capture on smart devices, phones or tablets; there is no eyepiece for visual observation.
Features
Opening: 50 millimeters
Focal length: 250 millimeters
Focal ratio: 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: 5Ah
Battery life: 3.5 to 5 hours
Connectivity: 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 set, ideal for traveling
- Works in 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 its integrated camera, featuring a 2.1-megapixel, 1920 x 1080 Sony IMX462 color sensor, well suited to the SeeStar’s 0.73 x 1.3 degree field of view. There is 64 GB of internal memory for storing astrophotos. Like other smartscopes, the S50 takes multiple short exposures and stacks them into finished astrophotos.
Features of the S50 include GoTo and tracking engines that can operate in altazimuth or equatorial mode, as well as 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 dew heater to keep the optics clear on humid nights. All of this comes in a compact, lightweight package weighing 5.5 pounds (2.5 kilograms) and measuring 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 material similar to Styrofoam, it holds up well. Inside is the plastic-bodied black S50, which looks more like a coffee maker than a telescope. The case also contains a carbon fiber tabletop tripod. It only raises the telescope 14 inches (355 mm) off the ground, but is usable. Finally, there’s a USB charging cable, a snap-on solar filter, and a brief instruction booklet.
Unlike conventional computerized telescopes, the S50 does not have a manual control. Everything is done from a phone or tablet, so the first step in getting 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 work on newer Apple computers with M-type processors.
ZWO SeeStar S50: performance
- The app contains easy-to-follow instructions
- “Tonight’s Best” offers an easy way to locate objects
- Bright objects like M42 are easy to see with brief exposures
The S50 doesn’t need much of a manual, as the app offers step-by-step instructions and tutorials. Turn on the SeeStar by holding the power button until the oscilloscope beeps twice, then release the button. When this talking glasses announces “On, ready to connect”, open the app and follow its instructions.
The SeeStar app offers several ways to select targets, including selecting them from a list of tonight’s best. An easy way to locate other objects is to use the built-in, comprehensive star atlas, accessible 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 box.
Once the nebula is displayed on the atlas screen, pressing “go to” sends the SeeStar to M42. When the telescope arrives at its destination, it takes images of the star field and compares them to the graphs in its memory (“plate resolution”) to make sure it is in the right place. It’s pretty accurate.
Then the app switches to a “live” camera view and autofocuses. A bright object like M42 is easy to see during brief exposures. Once focused, press the red “shutter” button at the bottom of the screen to start taking 10-second exposures (default). The target object will begin to “grow” as the exposures are added together.
In less than a minute, the SeeStar can produce a color image of the Orion Nebula that shows much more detail than can be seen visually in large telescopes.
ZWO SeeStar S50: Feature
- Connection via Bluetooth and WiFi
- The application may seem overwhelming at first, but you’ll quickly learn the ropes
- Can be connected to your home network
When using the S50 for the first time, it must pair with your smart device via Bluetooth. Once Bluetooth is enabled, the oscilloscope will connect directly to the phone or tablet via Wi-Fi. The next time you use the SeeStar, Bluetooth will no longer be required.
At first, the SeeStar app seems overwhelming, with lots of selections and options in unintuitive places. However, with a little experience, the process of taking astrophotos becomes easier. It would help if ZWO did not continue to modify the application to the point where it frequently has to be relearned. However, the telescope’s exceptional images deserve a little practice. The SeeStar itself poses no problems for such a relatively inexpensive instrument.
This direct Wi-Fi connection works well and is convenient for use on dark sites. At home, however, it is best to use “Station Mode”. This allows the telescope to connect to a home network rather than directly to a phone or tablet. In Station mode, your smart device can be used normally and does not need to stay near the oscilloscope.
Should you buy the ZWO SeeStar S50?
Is the ZWO SeeStar S50 perfect? Of course not, no telescope is; there are some problems. The main thing is that ZWO updates the SeeStar app very frequently. While adding new features is a good thing, bugs – sometimes serious – are also often introduced.
The SeeStar produces impressive out-of-the-box results in azimuth mode, but 10-second exposures (the scope can expose up to 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 mode or “EQ”.
In EQ mode, the SeeStar is tilted so that its body points roughly toward the north (or south) celestial pole. The app includes a built-in routine that allows the S50 to be precisely polar aligned. Using EQ mode, however, requires purchasing additional equipment: either a full-size camera tripod with a tilting head, or one of the equatorial wedges sold for the SeeStar. Under most conditions, EQ mode produces significantly superior images.
Who is the SeeStar specifically? not For? Those who are most interested in the Moon and the planets. Although it can produce beautiful full-disc images of the Sun (with the included solar filter) and the Moon, the planets will appear very small with only 250mm of telescope focal length.
If this product is not for you
If you prefer to see the cosmos with your own eyes rather than on your screen, you can’t go wrong with the highly rated Celestron NexStar 8SE, known as the world’s most loved telescope.
Read our full Celestron NexStar 8SE review
If you’d rather invest more in one of the best value telescopes money can buy, we recommend the Vaonis Vespera II. The images are stunning and it’s a very reasonable price compared to some of its competitors.
Read our full Vaonis Vespera II review
SkyWatcher SkyMax 180 Pro
Smart telescopes are typically designed for deep sky objects, so you’ll need a spotting telescope with a good aperture to resolve the details of the planets – something like the Sky-Watcher SkyMax 180 Pro.
