"With this review I am referring to the product ""K&F Concept Nano X-Series UV Filter 82mm Schott-Glass B270 28 Layers MC Super Slim"", which I purchased in January 2023 and now after a few weeks I would like to share my experience.

Background:
As should already be generally known, UV filters are no longer bought for UV protection these days, since no damage from UV radiation is to be expected due to various lens coatings. The UV filters are therefore usually only used as lens protection to protect the front element of an expensive lens against dirt and damage. In the event of damage, it can simply be replaced.
I therefore primarily wanted protection for my Sigma 24-70mm 2.8 Art and my Sigma 35mm 1.2 Art, which have the same filter diameter.

Positive:
I didn't notice any noticeable change in image quality in my tests. Both the sharpness in my test photos was the same as without a filter and I could not see any artefacts or disturbing light reflections. There are also several independent tests that compare the quality of UV filters - the K&F Nano-X does not show any major loss of quality, at least not in these either.
The ribbing on the outside of the filter is also very positive. This is (at least subjectively for me) actually helpful and creates more grip.
The box is also stable enough to safely take the filter with you to the place of use.

Neutral:
What is also often criticized with cheaper filters is the canting of the filter, which means that it can no longer be loosened. With my copy I could see differences between my lenses, but the filter always ran quite smoothly. At least I couldn't find any major problems. As you can hear in the attached video, it makes noises on my 35mm 1.2, but doesn't tilt at all.

Negative:
I didn't notice any points that would make me devalue the full number of points in a different way.

If this review and the attached pictures and videos were helpful, I would be happy to receive positive feedback ("helpful answer" button). If you have any questions, please leave them on the product page. I'll try to answer them there too!"

The protective filter came quickly and was well packaged. It is also packed separately in a practical plastic box, which you can use later if you switch between ND filters or UV filters, which I personally find very practical. The protective filter makes a neatly processed impression and can be easily rotated onto the lenses. I mainly use the UV protection filter as protection because I'm outside a lot. The lens glass is often splashed/covered with dogs and children, so I can quickly clean the protective filter with a cloth without worrying about scratching the actual lens glass. If the protective filter is scratched, you simply buy a new one instead of a new lens. I do have one downside though, if you take photos at night you have unwanted glare spots from the UV protection filter, so it depends on how you hold the camera so that it isn't too strong. When photographing during the day, with direct light (sun/lamp), I personally don't find the lens flare disturbing. It makes a clean processed impression, it protects my lens, which is my top priority, so I can recommend the UV protection filter. I find value for money very good.

Quality filters from K&F Concepts at an affordable price. The filter is slim and easily screws onto my lens. I experience no vignetting with this filter on my 18-45mm kit lens. The lens is clear and provides a layer of protection for my lens. The photos included show the photo taken with no filter attached (the one with the filter in the photo) and then the same shot after I installed the filter. No difference - exactly what I'm looking for. You can't go wrong with K&F concepts - high-end quality at a budget-friendly price.

With this review I am referring to the product "K&F Concept Nano X-Series UV Filter 82mm Schott-Glas B270 28 Layers MC Super Slim", which I purchased in January 2023 and now after a few weeks I would like to share my experience.

Background:
As should already be generally known, UV filters are no longer bought for UV protection these days, since no damage from UV radiation is to be expected due to various lens coatings. The UV filters are therefore usually only used as lens protection to protect the front element of an expensive lens against dirt and damage. In the event of damage, it can simply be replaced.
I therefore primarily wanted protection for my Sigma 24-70mm 2.8 Art and my Sigma 35mm 1.2 Art, which have the same filter diameter.

Positive:
I could not detect any noticeable change in image quality in my tests. Both the sharpness in my test photos was the same as without a filter and I could not see any artefacts or disturbing light reflections. There are also several independent tests that compare the quality of UV filters - the K&F Nano-X does not show any major loss of quality, at least not in these either.
The ribbing on the outside of the filter is also very positive. This is (at least subjectively for me) actually helpful and creates more grip.
The box is also stable enough to safely take the filter with you to the place of use.

Neutral:
What is also often criticized with cheaper filters is the canting of the filter, which means that it can no longer be loosened. With my copy I could see differences between my lenses, but the filter always ran quite smoothly. At least I couldn't find any major problems. As you can hear in the attached video, it makes noises on my 35mm 1.2, but doesn't tilt at all.

Negative:
I didn't notice any points that would make me devalue the full number of points differently.

If this review and the attached pictures and videos were helpful, I would be happy to receive positive feedback ("helpful answer" button). If you have any questions, please leave them on the product page. I'll try to answer them there too!

EVERY LENS SHOULD HAVE A UV FILTER FOR IMPACT PROTECTION. NOT THE BEST QUALITY BUT IT WORKS FOR A LENS I WILL ONLY USE 10-15 TIMES A YEAR. CANON R3

"Every lens should be equipped with a high-quality UV filter for protection. This 52mm Nano-X circular polarizer filter and MC UV protection filter kit from K & F Concept has such a filter. The kit also includes a circular polarizer filter and 2 high-quality lens caps. The 52mm UV filter has found its permanent place in my Canon EF-M 55-200mm STM lens with image stabilization, and the circular polarizing filter will serve as a welcome extra for several other lenses so I don't have to play "switch filters" between them. The included lens caps are very nice, but I find that it sometimes takes a bit too long to remove them, and I prefer the clip-on style that can be removed instantly.
Both filters improve image quality by removing glare and haze, respectively."

I have the UV protection filters on almost all of my 7 lenses. Not to reduce UV radiation, but to protect my lens glass. The UV filters arrive well packed in a plastic box. I can recommend the filters without reservation.

Protection for P900 lens