ZWO upgrades flagship Seestar smart telescope, adding new optics and twin 4K sensors

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ZWO has announced the release of the Seestar S50 Pro, a much-anticipated upgrade to its original Seestar S50 model that popularized smart telescopes in 2023.

Although this new all-in-one smart telescope remains a 50mm apochromatic refractor, its optics have been upgraded to a four-element apochromatic lens with extra-low dispersion (ED) glass, which is designed to improve star sharpness across the frame — especially in the corners — and reduce chromatic aberration. It's also got a slightly increased focal length of 260mm (f/5.2).

Another critical hardware upgrade is to a 1/1.2-inch CMOS sensor, which increases the resolution to 3840×2160 pixels (4K). The original Seestar S50 achieved 1920x1080 pixels (HD) from a native 1/2.8-inch Sony IMX462 CMOS sensor. It also has a 2.8-degree field of view, up from the S50's 1.46 degrees. Finished images are 8.29 megapixels, and it's now possible to put the 'scope into equatorial mode for longer, more stable exposures.

That's all in line with the upgrades seen on the more recent Seestar S30 Pro , as is the addition of a wide-angle lens. The S50 Pro has a 3840×2160-pixel (4K) quality wide-angle lens — based on a 1/2-inch CMOS sensor — with a 63-degree field of view. In addition to making it easier to manually find objects, the wide-angle camera can also be used to take nightscape images (such as of the Milky Way), create star-trail images and timelapses, and produce constellation images (with automatic identification and annotation).

Other hardware changes include a 67% larger battery (10,000mAh, up from 6,000mAh) for around nine hours of operation, and doubled onboard storage (128 GB). The Seestar S50 Pro can also now be networked, with the app adding several new built-in image processing tools. Three built-in filters — UV/IR cut, dual narrowband light-pollution (OIII 30nm / Hα 20nm) and a dark-frame — are also included.

In July, ZWO released a limited, numbered product, the Seestar S30 Pro Total Solar Eclipse Edition , to mark mainland Europe's first total eclipse of the sun since 1999, on August 12, 2026. It's essentially a black version of the standard Seestar S30 Pro , a smaller, more portable smart telescope, and an upgrade of the Seestar S30 .

The new Seestar S50 Pro comes as rival Vaonis releases its Vespera 3 and Vespera Pro 2 smart telescopes.

The Seestar S50 Pro is available for pre-order now for $999 / £899, with shipping expected to start at the beginning on September.

See our full guide to the best smart telescopes