K&F Concept 82mm Circular Polarizers Filter Polarizing Filter 28 Multi-Layer Coated Super Slim High Definition CPL Lens Filter (Nano-X Series)

I recently wrote a review of the K&F Series K CPL. The polarizer worked fine but my images were not sharp. I narrowed the issue down to it being the CPL I was able to return it with no problem. I've used K&F filters before and never had an issue so I figure I just got a bad one.However, rather than swap it for another, I spent the extra money and purchase the Series X polarizer which I received today. This one works beautifully. The ring turns smoothly with just the right amount of resistance so I know it will stay in place. My images come out sharp.The only issue I had was I used it in conjunction with a UV filter and I had a difficult time removing it. I read that it's not a good idea to stack filters with that as one of the reasons. I also read a review where someone also had difficulty and he simply turned the polarizer counterclockwise and was able to easily remove it from the UV. I'll try that and if I still have issues, I'll just use the UV filter when not using the CPL.The filter was nicely pack in its own plastic case and comes with three microfiber cloths. It was three times the cost of the Series K, but it was worth it! I've only had it one day and am very happy with it.BTW, the photos used in this review were not edited. I took them as RAW and exported to JPG.PS, I took Jim S’s suggestion about rotating the polarizing ring counter clockwise and he’s correct, it will loosen up. No specific number of turns but it loosens so it easily comes off. Thanks, Jim S.

I just received my 77mm CPL filter and after reading about the filter getting stuck on lenses I decided to try putting it on a 77mm UV filter that I had on my lens. It screwed on smoothly and as I rotated the filter clockwise (as seen from in front of the lens) to tighten it, it came to a bit of a crunching sounding stop as the filter was completely seated in the UV filter. Then I tried removing it. Nope, couldn't budge it as hard as I tried. I put the UV filter with the stuck CPL on my camera lens to try it out as a polarizer. As I was rotating the CPL filter lens counter clockwise (as seen from the front) all of a sudden the CPL became unstuck from the UV filter and screwed off easily. I repeated this several times and it worked every time. Stuck, rotate the CPL filter counter clockwise and it unsticks. I thought there might be a particular rotation where this would happen but it doesn't seem to be that way. This just may be my CPL filter copy but if you can't get it loose, just try rotating the CPL lens counter clockwise slowly and trying to see if the filter threads get unstuck. I gave the filter 3 stars because of this behavior but the optical filter itself seems to work well as a polarizer.I checked to make sure it was truly a circular polarizer and it was. My method for determining this is to look at my LCD TV screen through it from the side that is normally closest to the camera lens. As I rotate the filter the screen seen through the filter goes completely black. This is because the light being transmitted from the TV screen is linearly polarized and when the linearly polarized layer of the CPL is at a right angle to the polarization angle of the light, no light gets through. The "circular" part of a CPL is a layer behind the linear polarizer which converts light that goes through it from linear into circularly polarized light. DSLR focusing systems can be fooled if presented with linearly polarized light so this conversion to circular polarization avoids that problem. To make sure a CPL is really a CPL, turn the filter around so the side normally closest to the lens is towards the LCD TV screen and rotate the filter and you shouldn't see any diming of the image coming through the filter (if you do the circular polarizer layer is missing). This is because the circular polarization layer of the filter is now being hit with the linearly polarized light from the TV screen and it converts it to circular polarization. Circularly polarized light wont be stopped by the linearly polarized part of the filter, there will be some attenuation but it won't be a function of the rotation of the filter.A day later: I have increased my rating to 4 stars. I tested the K&F CPL against a much more expensive B&W CPL I have that I bought about 10 years ago and the K&F performed pretty much identically as far as the polarization effect is concerned but it has slightly less light loss. The B&W loses about 1.3EV while the K&F only loses about 1EV. In the process of my testing I put the K&F filter on and off the lens about half a dozen times and I saw the same result with the filter ring loosening from the lens as I rotated the polarizer slowly counterclockwise. For my copy of the CPL at least that is the secret. I never touch the ring that threads onto the lens once I have it installed. It screws off easily with the rotating part of the filter once the threads release.Edit 5/5/2025I was contacted the seller in April 2025, almost a year after my original purchase and they wanted to make sure I was a satisfied customer by sending me a new CPL filter with a magnetic ring, the filter and a magnetic lens cover. That product arrived and it looks great. I haven't had a chance to use it in the field yet but I have looked at the polarizing effect and it is very similar to the original filter I received which worked fine. I really appreciate their desire to have their customers completely satisfied! I am adding an additional star to my review as a result.

I use this K&F Concept 62mm filter for videography, and let me tell you — it’s an absolute game-changer. Whether I’m shooting in harsh daylight or trying to get those cinematic shallow-depth-of-field shots without overexposing, this filter handles it like a pro.The build quality is top-tier — solid metal frame, buttery smooth rotation (crucial for variable ND use), and the optics are ultra-clear with zero noticeable color shift or image degradation. I was honestly shocked at how clean my footage looked straight out of camera.Reflections? Controlled. Glare? Gone. Sky blown out? Not anymore. I’m able to maintain proper shutter speed in bright conditions without having to crank down my aperture or ISO — which is exactly what you want for smooth, cinematic motion blur.Also, bonus points for the slick protective case it comes with. Fits right into my gear bag and keeps the filter safe when I’m on the go.If you’re serious about videography and want professional-level control over your exposure and image quality without dropping hundreds, this K&F Concept filter is the real deal. Can’t recommend it enough.🎥🔥 Rock-solid performance. 5 stars all day.

As this is one of the more expensive CPLs it's pretty good. Hard to screw on/off but otherwise great. Does a good job. It actually saved my lens from being hit by a rock at the racetrack while photographing in car media. Going to buy another one now.