Although many professionals say not to bother with lens filters, I am clumsy and wanted to protect an expensive lens from finger-prints and accidental knocks. The three things that attracted me to this lens were a) the 99% transmission claim, b) the slim frame, and c) the price (not the cheapest, but not that expensive). On my 100-500mm lens, its use is subtle, but noticeable.

A minimally applied UV filter of very good quality and a sturdy storage box - I can only recommend it...
Not to be despised either: A sturdy round box for storage (including other filters not currently in use).

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 :)

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.

Made from high-quality materials. Precisely built. It offered the least amount of resistance I've had screwing on a new filter. It's very thin so it won't interfere with wide-angle lenses (as much as is possible).

Using a full-frame DSLR, I did side-by-side, pixel-level comparisons between shots with no filter and with this. One photo was a wide-angle shot the included sky on a high-UV day.

Results: well, I didn't see any difference in color or richness in the high-UV shot, so I wouldn't buy it just for that. Mostly, people buy these simply as lens protectors (and trust me, they've saved my bacon on a high-end lenses several times now!). As a lens protector, you want it to be as unobtrusive as possible and I am pleased to report that I can detect no significant difference with any test shot - color balance, sharpness, contrast - they all are so close that I could never say definitively that any minuscule difference was due to the filter.

A very high-quality product with (presumably) a good level of protection. The packaging and case also convey a feeling of quality and pride in their product.

I added this to my Canon Rebel T3i camera. The camera is a few years old and I love it. Cleaning the lens is always a chore, you have to get out the right cloth and make sure not to scratch it! But with this on, I can just use my shirt. If I scratch it, it was $20 and I can get a replacement. I'm really happy with that!

... and I can't say anything negative. I have several of them for different lenses and never had any problems

Very thin and light, it does not alter the color rendering

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.

Excellent quality/price ratio. The filter is the top of the range.