The original Seestar S50 did more than any product in recent memory to make astrophotography approachable — a single box that finds, tracks and photographs deep-sky objects without a mount, a laptop or a working knowledge of polar alignment. Its one real weakness was resolution. ZWO has now launched the Seestar S50 Pro, and that is precisely what it has fixed. Full details are on the official ZWO Seestar S50 Pro page.
Four times the resolution
The headline upgrade is the sensor. The original S50 used a 1/2.8-inch Sony IMX462 producing 1920 x 1080 images — fine for sharing, limiting for anything else, and the S50’s weakest specification against rivals. The Pro moves to a 1/1.2-inch CMOS at 3840 x 2160, so 4K.
That is a substantial jump, and not only in pixel count. A physically larger sensor gathers more light per photosite, which matters enormously in astrophotography where you are working with very little of it. Field of view also widens considerably, from 1.46 degrees to 2.8 — enough to frame larger targets like the Andromeda Galaxy or the North America Nebula that the original struggled to fit.
Better glass, too
The optics have been reworked. It remains a 50mm apochromatic refractor — still the largest aperture in the budget smart telescope class — but moves to a four-element design with extra-low dispersion glass, at 260mm focal length and f/5.2. ZWO says the aim is sharper stars across the frame, particularly in the corners, and reduced chromatic aberration.
Corner star sharpness is exactly where cheaper refractors show their limits, with stars smearing into commas towards the edges. If the ED glass delivers, it addresses the second most common criticism of the original after resolution.
Three filters are now built in: UV/IR cut, a dual narrowband light-pollution filter (OIII 30nm and Hα 20nm), and a dark frame. That narrowband filter is the significant one for anyone shooting from a town or city, cutting sodium and LED streetlight pollution while passing the wavelengths emission nebulae actually emit.
The unit can also be networked now, with new image processing tools in the app.
Our take
Smart telescopes divide opinion — there are those who feel automation removes the craft, and those who point out that it removes the barrier instead. We are firmly in the second camp. Anything that gets more people looking up and photographing what they see is a good thing, and the results these produce from an ordinary garden are genuinely startling.
The obvious caveat remains: this is not a serious deep-sky imaging rig, and ZWO does not pretend otherwise. Its highly integrated design is its appeal and its ceiling. But at this price, with 4K capture and better glass, it becomes a considerably more capable instrument than the model that started the category.
If you want one, it’s available at B&H.
ZWO Seestar S50 Pro: Specifications
Type: all-in-one smart telescope.
Optics: 50mm four-element apochromatic refractor with extra-low dispersion glass; 260mm focal length, f/5.2.
Sensor: 1/1.2-inch CMOS, 3840 x 2160 (4K).
Field of view: 2.8 degrees.
Filters: built-in UV/IR cut, dual narrowband light pollution (OIII 30nm / Hα 20nm) and dark frame.
Connectivity: Wi-Fi, with network remote access (free trial during beta).
Software: app-based control with new built-in image processing tools.
Predecessor comparison: the original S50 used a 1/2.8-inch Sony IMX462 at 1920 x 1080 with a 1.46-degree field of view and a 250mm f/5 three-element design.
ZWO Seestar S50 Pro: Price and availability
The Seestar S50 Pro launched on 25 August 2026 at a special launch price of $899, reduced from $999. The launch offer runs until 15 September 2026, and shipping begins on 1 September. UK pricing varies by retailer — check current listings before purchase.
