ZWO Seestar S50 Pro

ZWO Seestar S50 Pro: the successor to the most popular smart telescope

The ZWO Seestar S50 Pro is the new generation of the Seestar S50, the best-selling smart telescope of recent years. ZWO has updated virtually everything: a 50 mm four-lens apochromat main optics, two 4K sensors, a second wide-angle camera, a 10,000 mAh battery, and 128 GB of storage. Operation remains just as simple as with the S50: you set it down, open the Seestar app, and the telescope automatically searches, tracks, and photographs.

With four shooting modes, you can photograph nebulae and galaxies, the Milky Way above a landscape (up to 8K mosaic), the sun and moon, and daytime nature and landscapes. Everything is stacked and processed on the telescope itself, giving you a finished 4K photo directly on your phone. If you want more control, the S50 Pro also saves the FITS files for your own post-processing.

For those hesitating between the Seestar S30 Pro and the S50 Pro: the S50 Pro collects nearly three times as much light and has a 260 mm focal length compared to 160 mm. That means more detail on smaller nebulae, galaxies, and the moon. The S30 Pro remains the lighter travel model. If you are coming from the original S50, you can read in the S50 Alternatives Guide what the switch brings you.

50 mm quadruplet APO with a 260 mm focal length

The main optical system is a four-element apochromatic lens with an ED element, a 50 mm aperture, a 260 mm focal length, and a focal ratio of f/5.2. Compared to the triplet in the original S50, this results in sharper stars and less chromatic aberration at the edges.

Behind the lens is an 8.3-megapixel (3840 x 2160) 1/1.2-inch sensor with 2.9-micrometer pixels. That’s four times the resolution of the S50, with a field of view of 2.8 degrees. Autofocus, a defrosting system, and an internal filter wheel are built in.

Two 4K sensors, four shooting modes

In addition to the telephoto lens, the S50 Pro has a second camera featuring a 3.4 mm wide-angle lens (f/1.75, 6 mm focal length) and its own 4K sensor. The 63-degree field of view is designed for the Milky Way, star trails, and landscapes.

For each session, you choose one of four modes: Star Gazing (deep-sky), Starry Sky (Milky Way and star trails), Solar System (sun and moon), or Scenic (nature and landscape). The app handles exposure, stacking, and processing for each mode.

Smart processing while you watch

During live stacking, the S50 Pro improves the signal-to-noise ratio, applies dark frames, evens out the background, calibrates colors, and corrects stars. At the end of the session, a stacked, pre-processed 4K image or 8K mosaic is ready.

The app also includes a full-featured editing environment: removing or reducing stars, deconvolution, noise reduction, background extraction, and color calibration. ZWO does not use generative AI for this; everything is based on the data captured by the telescope itself.

Milky Way up to 8K, star trails automatically

In Starry Sky mode, the S50 Pro captures the Milky Way without a tripod head, tracker, or post-processing. You can choose from four framing options: 8K portrait, 8K landscape, 180-degree panorama, and standard 4K portrait. Foreground removal and the stitching of the individual shots are performed on the device.

You can capture star trails in the same mode: frame the shot, start the exposure, and the telescope will produce a photo and a time-lapse video when it's done.

Sun and Moon

The 260 mm telephoto lens frames the moon nicely and fully, with craters and mountain ridges in sharp focus. For the sun, you snap the included magnetic solar filter onto the telephoto lens and photograph sunspots.

Safety: Never point the telescope at the sun without the solar filter attached to the main optical system. Check the filter for damage before each session. The filter also serves as a neutral density filter for the wide-angle lens.

During the Day: Nature, Landscapes, and Time-Lapse

In Scenic mode, you can take 4K photos, videos, and time-lapses with both cameras, using manual gain and exposure settings. With the built-in intervalometer, you can capture a sunrise or a busy street.

Object tracking helps you keep moving animals in frame. Use the 260 mm telephoto lens for birds in the distance, and the 6 mm wide-angle lens for expansive landscapes.

Three built-in filters

The filter wheel behind the main optics contains a dual-band filter (OIII 30 nm, H-alpha 20 nm) for emission nebulae under light-polluted skies, a UV/IR cut filter for galaxies, star clusters, and the Moon, and a dark filter for automatic dark frames.

So you don't need to buy a separate filter to photograph mist from a city in the Netherlands or Belgium. The filters are designed for the telephoto lens; the wide-angle camera uses the magnetic filter as a neutral density filter.

Connect via NFC, Wi-Fi, or Bluetooth

A new feature is NFC: hold your phone up to the telescope, and the app opens with the connection already established. It also supports Wi-Fi at 2.4 GHz (longer range) and 5 GHz (faster data transfer), plus Bluetooth. The range is approximately 10 meters.

Use Station Mode to connect the S50 Pro to your home network. Then you can control it from inside your home while it's in the yard, as long as it's within Wi-Fi range.

Nine hours of battery life, 128 GB of storage

The 10,000 mAh battery provides up to 9 hours of recording and processing; the S50 had a 6,000 mAh battery. In freezing conditions, with the dew heater on, or when both cameras are active, the battery drains faster. Charging is done via USB-C and can be done during use with a power bank or AC adapter.

The internal storage has doubled to 128 GB, which is more than enough for 4K recordings, 8K mosaics, and FITS files spanning multiple nights. Files can be transferred to a computer via the app or directly via USB.

New tripod with adjustable leg angle

The included carbon-fiber tripod has adjustable leg angles. On uneven terrain, you can prioritize stability; on flat ground, you can opt for greater height. The three-point support keeps the telescope steady during long exposures.

If you want to use a longer exposure time than is possible in alt-azimuth mode, mount the S50 Pro in EQ mode on the optional ZWO TH10 tripod head. This allows for exposure times of up to 60 seconds per frame, which improves the signal-to-noise ratio for faint nebulae. EQ mode is not necessary for good results; it is an advanced feature.

Everything planned in the app

Based on your location and the time of day, the Seestar app creates a session plan featuring the best objects of the night. You tap an object, and the telescope pans to it, focuses, and begins stacking. Mosaic mode is available for large objects that don't fit within a single field of view.

You can share your results from the app or post them on the Seestar community. You can export FITS files for editing in Siril, PixInsight, or other software.

S50 Pro, S50, or S30 Pro: The Differences

Compared to the original S50: a quad-lens camera instead of a triple-lens one, 8.3 megapixels instead of 2.1 megapixels, a second wide-angle camera, NFC, a 10,000 mAh battery instead of a 6,000 mAh one, and 128 GB of storage instead of 64 GB. The S50 is no longer available.

Compared to the S30 Pro: the same sensors and software, but with a 50 mm aperture and a 260 mm focal length, compared to 30 mm and 160 mm. The S30 Pro is smaller and lighter, making it better for travel; the S50 Pro captures more detail from smaller and dimmer subjects.

Included

• Seestar S50 Pro smart telescope
• Carbon tripod with adjustable leg angle
• Magnetic solar filter (also serves as a dark filter for the wide-angle lens)
• USB-C charging cable
• High-density foam protective case

Featured accessories

The S50 Pro has a new housing. Accessories made for the original S50 (dew shield, filter holder, bahtinov mask) therefore do not necessarily fit. As soon as ZWO releases accessories for the S50 Pro, we will include them in our ZWO product range. For EQ mode, the ZWO TH10 tripod head is intended. A power bank with USB-C Power Delivery is a sensible addition for nights longer than the battery life.

For whom yes and for whom no

• ✓ You want deep-sky photos without the learning curve, with a finished result on your phone
• ✓ You live in the city and want to photograph mists without buying a separate filter
• ✓ In addition to deep-sky, you also want to capture the Milky Way, star trails, and landscapes
• ✓ You have an original S50 and want to make the move to 4K, dual camera, and longer battery life
• ✗ You want to look through an eyepiece yourself: a smart telescope does not have an eyepiece, so check out the Dobson telescopes
• ✗ You want to capture large images of planets: a 260 mm focal length is too short for that
• ✗ You are looking for the lightest travel model: then the S30 Pro the better choice

Specifications

Compare the S50 Pro with other models on our page with smart telescopes, or read the review of the Seestar S30 Pro for our experience with the same software and sensors.

You can find more products from this merk on the ZWO merk page.