I continue to be impressed by K&F Concept equipment. It's well-made, and the quality of the optical grade glass and the coatings are both really decent. I didn't notice any drop in sharpness.

A UV filter may help the look of some outdoor photos in bright sun, but honestly I can't see much difference. I use UV filters like most people do, as a way to protect the front element of my lenses. If you're shooting someplace where the lens could get stuff on it, like in the rain, at the beach (salt spray), or the pool (splashes), at a party where people might be getting sloppy with drinks or around kids/pets who might reach out and touch the lens, a UV filter is good protection. It's much easier to clean a filter than the element on an expensive lens!

Of course for this purpose you want a filter that won't degrade the quality of your images, so far as I can tell this one does not. I haven't noticed any visible darkening or color shifts, in fact when I first opened the box for a second I thought there wasn't any glass in the filter ring! So overall I think this will offer some protection to your lenses without changing picture quality. And of course, if you're someplace that isn't hazardous to your lens you can easily take the filter off.

While it's not a downside, I do kind of wish K&F would standardize their filter cases. I have received 3 different kinds already, and it would be nice if they had a stamp/sticker on the outside so you can quickly tell which type of filter is in the box! Luckily, I have a label maker.
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This is a great protective filter for a pricey lens. I recently ordered a set of diffusion filters from K&F Concept for one of my lenses and I was very pleased with the quality of the glass as well as the workmanship. I didn't hesitate to order this UV filter when it became available. I ordered the 55 mm version for a standard Nikkor lens that came as part of a DSLR kit. Years ago, I used UV filters on the lenses I used on my film cameras, but I am just now starting to learn my way around digital cameras. I imagine this might be helpful in some outdoor shots, but I was primarily interested in just protecting my lens. This filter is thin, light and attaches to my lens very easily. The optical quality of the Japanese-made AGC glass is very high. My images are sharp and I cannot see any aberrations in the glass. I appreciate that this filter is designed to be shock-proof, water-resistant and especially scratch-resistant as it is surprisingly easy to damage a lens or get it wet or dirty (and they aren't all that easy to clean). It is nice to keep dust off of my lens, and not to have to worry so much about something happening to it so I can just think about taking pictures. I have several other lenses in various sizes that are also in need of protective filters, and I will certainly be looking for this brand. I also like the sturdy storage case this lens arrived in. The current price of $32.99 is a very reasonable cost and such a worthwhile purchase so I know my expensive lenses are protected.

Speaking of myths, just what do UV filters do?

Originally, UV filters, and their cousins, haze filters, were placed in front of the lens to mollify the effects of UV light on panchromatic and color film, given its proximity to blue on the light spectrum. This is not an issue in digital photography.

Some (here) say a UV filter will prevent UV degradation of the lens or its coatings. Interesting but I have never heard this claim and could not find any knowledgeable photographer making it via a web search.

Some say a UV filter can protect a lens from breaking if dropped. Most photographers/lens manufacturers agree that today’s lenses are far more sturdy than a UV filter, which very well may break if the lens is dropped.

Some say a UV filter may cause flare or ghosting (especially in high contrasting scenes) in the final image. Most photographers report that such an occurrence, if it happens, is hardly noticeable.

For all intent and purposes in digital photography, UV filters serve one purpose: prevent scratches and foreign matter from coming into contact with the front element of the lens. The point being that dust, sand, saliva, sweat, rain, snow, salt spray, et al., are easier to clean from a filter than a lens, while saving the lens from relentless, potentially abrasive cleaning regimes.

I obtained this filter to test for chromatic aberrations, flare, and ghosting – while using it for lens protection. I did not notice any significant effects. If I wish to be picky, very high contrast scenes (bright lights on a dimly lit street) may evidence a bit of ghosting. The filter is well-made, sturdy, and has no visible flaws in the glass or coatings.

Without meaning to demean anyone, I suspect that the average photographer would not recognize any ill effects in their images due to this filter. I obtained the 72 mm which I recommend without reservations.

In modern DSLR cameras, there is a huge argument whether UV Filters provide any benefit. I’m in the camp that says there are definite benefits. First, there are arguments that the UV filter can protect the sensor in your camera from long term deterioration caused by UV exposure. Second, a high-quality filter provides a layer of protection to the front of your camera lens. I was taking pictures at a very windy venue, and a door was caught by the wind and smacked the front of my lens before I could catch it. I was lucky that the hit wasn’t worse, but the lens did receive a small chip to the front plastic. This filter is made out of metal, screwed right on, and will protect the front of the lens from this kind of damage in the future. The lens could still get damaged in other ways, but it is a layer of protection from these unexpected bumps. In the future, if the lens gets bumped and the filter gets destroyed, I’ll be grateful that the filter took the hit instead of the lens. The filter is much cheaper to replace!

This has helped with UV protection during the day and has also helped prevent scratches to my camera lens. It is very slim and you can barely tell that its on. I am also able to put my lens cover on it so that it does not get damaged. Worth the investment

K&F makes solid filters, and this UV filter is no different. My 24-70 has been naked for some time and I decided it was time to get it a protective UV filter as I've brought it back into my rotation of travel lenses, so I ordered a matching 77 mm filter. The K&F filter surprised me when I first unboxed it. First, the case is fantastic. It's a hard-shell smoky-transparent plastic case that is secured with 4 tabs and a short rotation to lock and unlock it. It's a large filter case because the same case accommodates 82 mm filters, but it will also accommodate smaller filters down to 43 mm. And the filters won't slide around. But how? Inside the case are two conical sections of silicone, a small one with 2 ridges and a large one with 10. The large one has numbers next to each ridge indicating the size it fits (43, 46, 49, 52, 55, 58, 62, 67, 72, 77, 82). The small one with 2 ridges is meant to hold the opposite end of the filter and stabilizes it. So as long as your filter is one of those listed sizes, it should fit in this case and is held securely in place due to the silicone ridges. Now, it's held my single-layer filters without issues, but it doesn't accommodate my variable ND filters or filters with rotating handles/extensions that jut out.

The filter itself is very well constructed. The aluminum body has two sections of thick knurling built in so it's easy to grip the filter for installing and uninstalling. The filter itself doesn't noticeably impact my image quality on my 24-70 compared to without the filter when I examine an image up to 2x in Lightroom, and I don't notice a significant color cast either. For me, the K&F UV filter is well-constructed and good to use.

Thoroughly enjoyed adding an extra layer of protection to my lens from the elements. The protector didn't effect my image quality or auto focus. It provided a high quality image.

I put one of these on every one of my lenses. This is the best quality filter I've ever purchased - I'm impressed with the clarity, the glass, the ease of screwing it in. Loses a star because the case it comes in is HORRIBLE to put back together, and in fact I ended up throwing it out and using a case from a competitor filter.

UV Filters are commonly used to prevent extended UV rays on the front element of a lens, and as a long time photographer, I recall the days when a UV filter was kind of a must-have, for protecting your lenses, long term... or at least that was the theory.

Unfortunately, much of that belief still continues to this day, and while the merits of a UV filter offering protection, are still very much a hotly debated subject, UV filters DO offer one very good benefit... they keep dirt/grime/fingerprints off the main front element of a camera lens.

In case of wedding photography, it's not that unheard of for a child/baby/drunk-adult to reach out and attempt to touch your lens... in fact, the attempts to do so, can produce some of the most incredible shots, if timed right.

However, the cost and difficulty to clean a good high end lens, is often a scale harder than simply cleaning a lens cover on the front... which is where UV filters tend to come in... they do a good job of keeping direct contact off of the actual lens.

I've used many different types of filters over my decades of photography, and among those, UV filters are probably the ones that have the most quality range with them.

This is the first K&F filter I've used, and I've been using it on a Sigma ART lens for the last week.

I'm happy say, this filter is a nice middle to upper range UV protector. Unlike so many of the cheaper UV filters, this one doesn't seem to introduce any readily noticeable color shift, or image distortion with the image.

While I'm sure, if I start pixel peeping, and comparing this UV filter to a >$200 one, I could probably find a few flaws here and there.. the fact is, this filter is half the cost of many of the other upper middle range filters.

... and lets face it. A UV filter's primary goal, is protection. It decent UV filter shouldn't be altering your images in any noticeable way. So to that end, this product does EXACTLY what it's supposed to do.

One thing the K&F DOES excel in, however, is the case the filter is packaged in.

The case is a hard cylindrical case, with an easy twist open. However, the nicer aspect of this filter, is the fact that the case has a silicone ring, with grooves in it, that holds the filter in place, while inside the case. This is something that many other manufactures DON'T do (including a large number of rather high end filter manufacturers)

While yes, this is the first real experience with a K&F Filter, for me... after looking at the attention to detail they've done, I'm now in the market for a few others of theirs :)