Objectively speaking, one might wonder what exactly justifies this price: a filter that many photographers use only as "lens protection," and whose effect is usually not even visible in the photos. But this line of reasoning, in my opinion, falls short. The Chinese manufacturer K&F (or Kentfaith) is no longer a cheap provider. Its product range, and thus its expertise, includes not only UV filters but also other filters (CPL, NDF, etc.). Thus, this filter comes from a group that puts a lot of thought into how to build even better filters. And you can tell that with this X-Pro filter even from the packaging:

This filter came elaborately packaged suitable for gift giving. It also looks great with a gold colored inlay showing its pedigree. Please see the image that’s part of this review for a look at part of the gold colored lettering.

It sure does look the part. I tried some test shots with the filter on and off the lens and then did the best pixel peeking I could noting no difference in exposure or color cast. To be fair, I’ve never noticed this with any high quality filter. I’ve never bothered with bargain basement filters because I have no interest in Lomography or its related ilk.

The manufacturer says this is thin and it is. Please see the image where I compare this filter with another UV that costs less than half as much. Both seem thin to me. I don’t see how thickness makes that much of a difference because adding any filter will require the removal of this one or you’ll get image quality robbing refractions from between the two filters.

I considered using a micrometer to measure the thickness of the lens itself but gave up the idea because I had no way to assure that I’d not scratch either this or another filter I’d use for comparison.

In sum, this does work well as a UV filter and it does not in any way alter the images when compared to the same lens without this filter attached.

I don't normally use UV filters because they have no function, they are only there to protect the lens glass from scratches and dirt.

However, it makes little to no sense to screw a cheap UV filter onto a cheap lens, because cheap filters in particular often worsen the image quality, but definitely do not improve it.

Exception:
I protect a high-quality lens (in my case one for €1500) with a UV filter, but of course this should also be high-quality.

And, I can say it right away:
This UV filter from K&F Concept from the Nano-X Pro series is absolutely recommended for this, because it is actually high-quality.

The packaging already suggests this:
The filter is in a chic black box in a pretty case with a magnetic snap closure.

The filter itself also leaves a very high-quality impression.

It is very thin, and can be screwed on and removed very smoothly.

I could not see any impairment of the image quality in several comparison photos.

Therefore, contrary to my usual habit, this useful UV filter will now remain in front of my premium lens as protection against dust and scratches.

Even if the price seems quite high, the investment can be worthwhile for high-priced lenses.

I give this filter a well-deserved 5 stars.

If I'm honest, I've always relied on established brand manufacturers such as B&W or Rodenstock when it comes to filters. I do have a few filters from Kase and K&F in my inventory, but I hadn't really considered Asian manufacturers when it comes to filters. And that's exactly what K&F wants to change with the Nano-X Pro series

The K&F UV filter comes in very attractive, high-quality packaging. The packaging also includes an additional leather case with a magnetic closure. A strap helps you pull the filter out of the case, so you don't have to touch the glass with your fingers. The filter is easy to attach; the thread is excellently crafted; the filter glides smoothly through the thread when screwed on. There's nothing to complain about in the photos; the quality is still top-notch. I give this fantastic, high-quality UV filter 5 stars. ⭐️⭐️⭐️⭐️⭐️

The K&F UV filter comes in a beautifully made box, which is then wrapped in plastic for protection. As a little gimmick, the insert and an enclosed cardboard part can be used as a small picture frame, if desired. The lens itself is stored in an anti-scratch bag in the storage case. This is an eye-catcher in itself, made of genuine leather and really well made. It also comes with a sealed microfiber cloth for cleaning and removing dust before installation. The filter screwed onto the lens without any problems; there was no jamming or wobbling; simply well-made. Whether a UV filter is necessary on a DSLR camera is a matter of debate. Let's put it this way: I haven't noticed any negative effects on the images so far. Especially with the 82mm lens size, the asking price of around €150 quickly becomes relative. Better a scratch on a filter than a scratch on the lens, which would require an expensive replacement.

This filter, if nothing else, helps keep my marriage on an even keel.

Now I won't rehash the old UV vs non-UV filter debate, but personally I don't really feel I need a UV filter on my DSLR lenses, and if I were the only person using my cameras I wouldn't bother at all as I'm extremely careful with all of my equipment. My wife, on the other hand...

Every time my wife takes out one of my cameras she treats it the same way she treats her sunglasses (lenses down on the dashboard of her car, jamming them in her pockets without a case or a second thought, smudges... just... everywhere. Oh, the humanity). When it comes to optical equipment she's history's greatest monster, a true menace to glass, but complaining about this to her will only ever end in a resentful argument.

So the solution? A high quality UV filter that will protect my lenses without reducing image quality. I've tried cheap filters in the past that I've ended up removing every time I take a shot because there's noticeable degradation in the results, but as this is a high quality filter I can't see any different in the final product with or without the filter. All I see is a clean, scratch- and fingerprint-free lens coming back to me safe and sound, and that's worth its weight in gold.

Super Sav, seller very concerned about the quality of his products
Good filter on lenses type 24-70 f2.8
Very strong vignetting on a canon rf 24-105 f2.8 lens at 24mm Z series (disappears around 35mm) in addition to a UV filter - but same problem with other brands of filters. To be used without UV filter on this lens

I ordered the K&F Concept Nano-X PRO series UV filter to use with the Pentax HD DA★11-18mm F2.8 ED DC AW lens. I generally use my high-quality lenses without a UV filter. Ultimately, every additional piece of glass in the optical path impairs the quality. But in dusty weather or even in the rain, using a UV filter is definitely a good idea, as you can then dry the filter with a cloth or remove any dust. If the filter gets scratched, the front element of the lens is still undamaged. Now, to the filter. The K&F Concept Nano-X PRO series UV filter comes in rather elaborate packaging. The filter is in a pouch, part of which is even made of real leather. The closure is magnetic. There is a strap on the side of the pouch. If you pull this strap, the filter slides out of the pouch. Also included is a cleaning cloth and a cardboard stand (?). I don't understand the point of this. Perhaps it's intended for display purposes by dealers? The filter is "Made in China." There's a German importer's address on the box. The filter easily attaches to my Pentax HD DA.★ 11-18mm F2.8 ED DC AW lens. There's nothing to complain about. The Pentax HD DA★ The 11-18mm F2.8 ED DC AW lens is not shaded by the filter. The workmanship of the filter is also really good. I took a few test photos with and without the filter and did not notice any negative effects. Under normal conditions I don't think the image result will deteriorate much. There might be problems with light reflections in backlit photos if the sun is at the right angle. But that would be a general problem with filters on lenses. Conclusion: The filter is really good. The current price of €149 for the 82mm filter is certainly anything but a bargain. Ultimately it doesn't make sense to buy a lens for around €1500 and then screw a cheap filter onto the lens, which then leads to poorer image quality. I give the filter 5 stars.

The packaging alone is enough to create the first wow factor - and it is not a "diversionary tactic" for poor quality.

This filter is super light and thin. It fits like a glove and is easy to screw on. It is particularly impressive in wide angle. You can see a clear difference in image sharpness. The whole photo looks crisper and has more contrast than with our previous UV filter (also a good branded product).

We have not tested how scratch-resistant or waterproof it is. But I think it is top quality through and through. My husband deliberately took similar photos with this and the previous filter and we compared them. The difference was unmistakable.

Due to this really good quality, the price/performance ratio is also good. The great packaging with leather case etc. is a nice goodie for us. If you want to give this filter as a gift, this "goodie" is of course great because the recipient can see from the first moment that they are getting something special.

We definitely recommend buying it and give it a full number of stars