Serounder 37mm 0.39X Professional HD Wide Angle Review

The Serounder 37mm 0.39X lens is a bit of a puzzle. It's a wide-angle adapter, not a standalone lens, that screws onto the front of your existing Canon EF lens to give you a super-wide field of view. It weighs just 119g, which is great for travel, and its versatility score is off the charts in the 99th percentile. That's because it promises to fit DV cameras, phones, and your DSLR, all for about $54.

But you have to read the fine print. Its core optical performance sits in the 34th percentile, and it has no autofocus or stabilization of its own. It's entirely dependent on the lens you attach it to. So while it can 'increase spatial depth' and capture wider scenes, the actual image quality is a big question mark that hinges on your primary glass.

Let's talk numbers. This adapter's job is to widen your view, and it does that by offering a 0.39x magnification factor. In practice, that turns a standard lens into an ultra-wide. But the performance story is defined by what it lacks. Its autofocus capability is in the 47th percentile, which is basically average, but remember, it doesn't have AF motors—it just passes through your lens's focus. Stabilization is worse, at the 39th percentile, and again, it provides none. Where it really struggles is in specialized areas. Bokeh quality is down in the 27th percentile, and macro performance is abysmal at the 17th. This isn't a lens for creamy backgrounds or close-up details. It's a one-trick pony for making your scene wider, and the optical quality of that trick is middling.

At $54, the value proposition is simple: it's cheap. You're getting a wide-angle effect for the price of a pizza. Compared to buying a dedicated ultra-wide prime lens, which can cost hundreds, it's a steal. But you get what you pay for. The Viltrox 35mm f/1.7, a proper autofocus lens, costs about three times as much but offers vastly better optical performance, a fast aperture, and full functionality. This Serounder adapter is a budget hack, not a quality investment.

Stacking it against real lenses shows its limits. The Viltrox 35mm f/1.7 Z, even though it's a budget prime, runs circles around it. The Viltrox has a fast f/1.7 aperture (this Serounder's aperture score is 29th percentile), real autofocus, and is a sharp, standalone lens. The Meike 35mm F1.8 is another proper lens that offers better build and optics for not much more money. Even the Yongnuo 35mm F1.8 for Sony E, while not a top performer, gives you a consistent focal length and autofocus. The Serounder can't compete on image quality. Its only advantage is price and that wild versatility score, but that comes with a massive optical compromise.

Here's the deal. If you're a traveler on a razor-thin budget who uses a Canon DSLR and desperately wants to try ultra-wide shots without buying a new lens, this $54 adapter might be a justifiable experiment. Its 99th percentile versatility and light weight are legit perks. But for nearly anyone else, it's a hard pass. The optical performance is too much of a gamble. Save up for a used Viltrox or Meike prime. You'll get a real lens with reliable quality, not a plastic tube that might make your photos worse.