Very wide range variable polarizer. I end up using this filter to get a few eclipse pictures, when the camera display only showed black with the high neutral density filter I bought specifically for the eclipse.

it works as advertised

K&F Concept filters are always of very high quality. I haven't had a neutral density filter yet. That's why I'm happy to be able to test it.

Even the packaging is of very high quality and the included leather case is very nice and sturdy. The filter can be easily pulled out through the band. The flap of the bag is magnetic.

Thanks to the small orange handle, the filter is infinitely easy to adjust. The effect is astounding. It helps to adjust the exposure comfortably in a wide variety of lighting situations. I mainly use it in lighting situations where I want to shoot with an open aperture and daylight is too strong for that. The colors in the image are not negatively affected by the filter.

Great filter for a decent price. 5 stars from me.

Exactly as advertised

⭐️ Rating: 5.0 out of 5.0 ⭐️

Workmanship: ⭐️⭐️⭐️⭐️ ⭐️
Variable: ⭐️⭐️⭐️⭐️ ⭐️
Practicality: ⭐️⭐️⭐️⭐️ ⭐️
Material quality: ⭐️⭐️⭐️⭐️ ⭐️
Price: ⭐️ ⭐️ ⭐️ ⭐️ ⭐️

Recommended purchase?

Bought two of these and taped them together to take pictures of the Annular eclipse last October. I got some pretty good photos!

This is a very well made filter. It's metal construction with a very well dampened outer ring. I like to shoot wide open on fast lenses outdoors in bright light. I'm not able to do so without a ND filter. This filter has a lot of variation in filter density. The photos I take have a nice natural color. Other ND filters I've used had a cast to the image. At least to my eye they did. This one is perfect.

Es un excelente filtro, me gusta como se gradúa y es fácil de usar y adaptar al lente de mi cámara

I needed a variable ND last minute that fit 67mm thread, and this was available for same day delivery. So I pulled the trigger. Normally, I buy high-quality filters like B+W, Breakthrough, Haida, or Heliopan. So I was apprehensive about this one, especially being a variable ND. But I was thoroughly surprised.

First, I LOVE the tab. It makes it so much easier and nicer to adjust the strength than trying to grip the edges of the ring. Second, I didn't notice any issues with color shift. Maybe if I shot side-by-side with the filter and without I would notice some, but it's nothing major. Even the best variable NDs have some color shift.

I didn't use it at its strongest setting so I'm not sure about the dreaded "X" pattern, but I always avoid the strong end with variable NDs.

I only wish it had hard stops at each end. I'm not sure why that isn't standard for every company.

Attached is a photo taken with the filter on an OM System OM-1 + Panasonic Leica 12-60/2.8-4. ISO 200, f/6.3, 15 second exposure.

What struck me, even before seeing the filter, was the attention to detail with regards to the packaging. Starting with a beautifully crafted box, a handy protective leatherette case in which the filter came wrapped in a small plastic protective pouch. The filter is made of quality materials: a metal frame with two hard rubber grips: one grip to secure the filter to your lens and a second rubber grip to select the perfect neutral density for your lighting situation: not too loose, not too tight. The addition of a large tab on the ring makes it easy for your fingers to quickly rotate the filter and avoid twisting the filter right off the lens. But most importantly, this product is constructed with high quality optical glass. The results? After multiple tests shooting photos and videos, there were no signs of vignetting in the corners and no visible image distortion. And no “X” pattern throughout the entire density range. Wow, this company goes all out to show how serious they are about making quality products. I’m very happy with my purchase!
EDIT: After thorough testing outdoors in bright daylight, I did notice some slight vignetting at the “darkest” setting. Seeing as I shoot mostly landscapes, this is really not an issue for me.