[52 mm] I am a film photographer and I bought this for my Pentax f/1.4 50mm lens to shoot long exposures of waterfalls. For such a low price I was prepared for problems but all of my images were beautiful and consistent, no difference in picture quality at different exposure times and different lighting conditions. The fact it is waterproof was greatly appreciated since the spray radius off some of the falls was quite impressive. Overall very pleased especially for the price, I would def buy from this brand again.
Good to note: I primarily shoot black and white, and the only color shots I took with this filter were at night, so I can't really speak to how it might affect colors. What I did shoot looked accurate and I don't see any discoloration.

[Aluminum] Completa menté complacido desde él cervical asta la calidad del producto

[Aluminum] I recently purchased the K&F Concept 1/4 Black Mist Filter from B&H, and it has quickly become one of my favorite photography accessories. This filter adds a touch of enchantment to my shots, softening highlights and infusing them with a subtle misty quality. It strikes the perfect balance at 1/4 strength, preserving critical details while creating a dreamy atmosphere. B&H's seamless shopping experience and prompt delivery made the purchase a breeze. I'm thoroughly impressed with both the product and B&H's exceptional service. The K&F 1/4 Black Mist Filter has unlocked a new dimension of creativity in my photography, and I couldn't be happier with my purchase.

[Aluminum] https://youtu.be/PexWWSgvwDE?si=d7Hr_YQ3kgdMz14u
You can see how it works on our youtube channel.

[Glass] I purchased this in 86mm, it's one of the few that comes in that large a size. Solidly built, super dense, beautiful, smooth rotation polarizer, although a bit rough on the treads when screwing on to lens. Solid locking plastic case. Works perfectly. My biggest gripe is that due to pandemic supply issues it took 6 weeks to arrive from China, where K&F is made. Well worth the price when compared to multiple polarizers.

[0.19 lb] A filter like this is a MUST HAVE if you want to level up how your images (for photography and video) look in broad, intense daylight in one fell swoop.

They reduce the overall amount of light coming in the camera so you can stop down for a beautiful optically blurred out background and heavily reduce intense sunlight reflections, virtually adding dynamic range in daylight. I knew this would help my shots but my jaw dropped when a got the footage back from testing locations for a project, with and without. (attached photos are screen grabs of video. Shot on Sony A74, Sigma 24-70 f2.8) *Note: This is my first ND filter and first polarizer.

My testing has found a slight cyan cast in the area where sunlight can hit the lens where shadows can be seen, it looks almost dreamy and I kind of like it, but not perfectly color preserving. With Nano-X Pro, I have not encountered any dark X pattern no mater how I adjusted it, which is far better than most Variable ND + Circular Polarizer filters on the market. The included pouch is made of materials that feel great in the hand and its pull tab that makes the filter rise out of the pouch is a very nice touch that makes me wish K&F Concept included this pouch with more filters and also sold separately. I want other filters in these things! (Wile they do sell other pouches. They do not sell the ones included with these filters.)

If you are on the fence and don't have a ND or polarizer, just get it. It took a while for Polar Pro to finally release something like this, and the price of this one STILL undercuts it. If you are a videographer/photographer, image quality is super important and this is a fantastic tool to help you properly expose your shots. There is a reason why Directors of Photography have built in ND filters on their wish list for their cinema cameras and this is why, it makes their job so much easier and allows them to focus on building the look that they want.

[Aluminum] Purchased the 95mm version for my OM 150-400 lens. Even using it atop the Olympus protective filter there's no loss in image quality. Also very effective polarization, more so than other more expensive polarizers.

[Aluminum] Bought specifically to use with my GF lenses for the Fuji GFX 50r. Truly does give a more filmic look right to the RAW files. Great for back light and creating natural lens flare. Skin texture is lovely as well.

[Glass] The K&F Concept Nano-X Filters are well made. I've purchased two 67 mm and one 77 mm and all three fit my lenses perfectly. Optically they have no practical effect on image resolution or light transmission and produce no added glare. These are well-made, reasonably priced filters with exceptional optical performance. It's amazing how much multi-coating technology has improved in the last decade and K & F seems to be fully competitive with the best filters available anywhere.

[Aluminum] Works great with Leica D-Lux 8