This isn't the first product I've tested from K&F Concept, and I'm starting to get to know them well, and each time, it's a solid product. It's not ultra-high-end professional gear, but for demanding amateurs, the price/quality ratio is often excellent. I've never been disappointed by them, and this filter is confirmed.

I was looking for a UV filter that would both protect my lens (Olympus Pro 40-150mm F2.8 mounted on an OM SYSTEM Om-1 Mark II) and not impact image quality, and this one pleasantly surprised me. I got it at 62mm for a zoom I use a lot outdoors, and it definitely does the job.

First of all, the build quality is impeccable. The frame is made of aluminum, lightweight but sturdy, and the ring screws on without forcing. The glass seems of good quality, and the coating works. It's a nano-coating, supposed to repel water and fingerprints, and limit reflections. And in practice, it works: no ugly halos or weird flares to report, even against a somewhat direct light source.

I compared the filter with and without it on several different outdoor shots, and I didn't see any loss of sharpness or contrast. The reflectance curve (seen on their product sheet) confirms this: over 99% of the light passes through, so there's virtually no loss in the final result, even in 4K or on demanding sensors.

The filter is also advertised as scratch- and impact-resistant, with a glass hardness rating of 9H. Okay, I'm not going to play the tester who tries to scratch their product, but it has already survived being transported without a case, in my camera bag, without a single mark, so that's a pretty good sign.

In short, this is a great choice if you want to protect your lens without compromising the quality of your photos. You don't need to be a pro to appreciate it, and it prevents damage to a lens costing several hundred euros. Sure, it costs a little more than a basic filter, but here you're paying for real optical quality, and it shows.