My gear: Canon 90D 18-135mm 3.5/5.6 USM lens.

I really love this cover. I've never had an ND filter before, but the features of this filter totally blew me away. As you can see from the photos I uploaded, they work wonders in filtering out the harsh light of daytime shots, and I can capture a pretty awesome sunrise with it too! I haven't used them for motion photos yet, as I usually do landscape photography, but they do help with images during the day to prevent your images from having overexposed areas. The included case is also top notch, is made of nice leather and is easy to take out of the box when you want to use it. I didn't notice any white balance issues, but I take all my photos in RAW so I don't usually pay much attention to my white balance (I fix that in the editing process). The lens itself is also of excellent quality. It is very easy to adjust and fits my lens well. I can't say enough about this filter. If you are looking for something to take your photography to the next level, this is an excellent starting point!

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.

My equipment: Canon 90D 18-135mm 3.5/5.6 USM lens I really love this cover. I have never had an ND filter before, but I am completely blown away by the features of this one. As you can see from the photos I've uploaded, they work wonders in filtering out some of the harsh light from day shooting, they also let me capture a pretty awesome sunrise! I have not used them for motion photos, yet, as I typically do landscape photography, but they do help with pictures during the day to avoid having overly exposed areas in your pictures. The case it comes with is also top tier, made with nice leather and easy to remove from the package when you're looking to use it. I have not noticed any white balance issues with it, but I take all my photos in RAW format, so I don't usually pay much attention to my white balance (I fix that in the editing process). The lens itself is great quality, as well. It adjusts very easily and tethers nicely to my lens. I cannot speak highly enough about this filter, if you are shopping for something to bump your photography to the next level, this is an excellent place to start!

have never really liked VND filters. I usually prefer fixed NDs. This K&F VND has changed my mind. It has exceptionally build quality. It is completely clear throughout its turning range. K&F also include a very nice case. Overall its fantastic.

Rating: 5.0 from 5.0

Quality of workmanship: ⭐️⭐️⭐️ ⭐️
Variable: ⭐️⭐️⭐️ ⭐️
Suitability for practical use: ⭐️⭐️⭐️ ⭐️
Material texture: ⭐️⭐️⭐️ ⭐️
Price: ⭐️ ⭐️ ⭐️ ⭐️

I was allowed to test the variable ND filter (gray filter) ND3-ND1000 of the brand K&F Concept.
For me it was the first contact with a variable filter.
Accordingly, I was over the large width of the setting of 1.5 - 10 f-stops by just moving the hand lever.
As an amateur photographer, I use a variety of filters up front that I carry with me on occasions like our vacations. It may not be the same for others, but I always sweat blood when changing screw-on filters in the middle of the field, scrupulously careful not to paw at them with my fingers. As of now, the camera case is a bit lighter and it stays with a single filter. I like that already very much.
But the filter was also already delivered in a valuable box, in which there is a noble bag as storage for the filter. I guess every hobby photographer is very happy about such a noble gift. But before buying, you need to know the diameter of the lens thread you are using. In my case, I ordered the filter for my normal lens that requires a 58 thread size. On the other two lenses, 63 filters would then be used.
In testing, I was thrilled with how easy it was to adjust and the quality of performance and workmanship is exemplary. Only, it would be nice if the setting had a min-max limit. So I had to always once briefly direct an eye on the lever, whether it is also in the adjustable range.
But this is complaining at a very high level. In any case, I am happy about this great filter and that the eternal change finally has an end.

Conclusion:
Very well made, variably adjustable ND filter (aperture 1.5 -10). Recommendation!

I hope that I could be of some help to you with my review. Thank you!

I already have a variable ND filter, but I am not satisfied with it because the dial is stiff and the results do not meet my expectations.

Already sworn off ND filters I came across a product review for this K&F filter, which convinced me so much that I ordered this filter for my new lens (Tamron 35-150mm 2-2.8f).

Already with the packaging (high quality cardboard box with magnetic holder) and then the insert decorated with gold and then the leather bag for storage has gradually introduced me to a high class product. The filter was delivered dust free, has visible coatings and a really usable adjustment wheel to dynamically adjust the filter. The screw thread is flawless and the first results are much better than the tests with the rather simple filter.

I am satisfied, but expect this performance at such a high price. Highly recommended!

I ordered this K&F Nano X-Series Variable ND Filter ND3-ND1000 (52mm) for my ""always on lens"".
The filter arrives very nobly packaged, including leather bag at home.
I tested the filter on my 28/2.8, it screwed on without any problems, also the adjustment of the strength works great due to the very pleasant resistance and the integrated nose. The filter does not produce color casts or image errors. The ND3-ND1000 is a perfect companion for me for open aperture photography in daylight/sunshine to long exposures, so it is very flexible for me to use.
I can definitely recommend this filter due to its very good quality (processing/image quality).

Many greetings
Holgi

Ah, the variable ND filter from K&F Concept—strong in the ways of the Force, it is. Crafted with the precision of a lightsaber duel, its Japanese AGC optical glass, multi-coated with 28 layers, shields against the dark side of glare and reflections. Clarity, it bestows. The putter adjustable design, clever it is. Like a Jedi adjusting his focus in battle, one may fine-tune the stops with ease, rotating the frame with the grace of a master wielding his blade. From ND3 to ND1000, versatility this filter grants, useful across many landscapes and scenarios. Waterproof and scratch-resistant, it is. Strong against the elements, it stands. Oil-proof and hydrophobic, like a Jedi’s robes repelling the chaos of the galaxy, this filter remains resilient through the trials of adventure. Vignetting, it does not—unless the wrong lens thou useth! A slight dark "X" may appear, but turn the frame, and balance in the Force is restored. Turns water into smooth, wispy trails even in bright light, this filter does. Like the flowing energy of the Force, movement transforms into an ethereal dream. But heed this warning, young Padawan—manual mode, you must use. Settings to Master the Force of the Filter: Shutter Speed: Slow, you must make it. 1/4s to 30s, depending on water’s movement and light. The longer the exposure, the smoother the trails. Aperture: f/8 to f/16 is wise, for clarity and depth, it ensures. But adjust, you may, depending on conditions. ISO: Keep it low—100 or 200, lest noise disturb the balance of your image. Focus: Manual focus, use. For sharpness, a Jedi does not rely on the camera alone. Also works great at night, it does! For streaking lights as they pass by, perfect it is. Speeder bikes on Endor, landspeeders on Tatooine, or city streets in Coruscant—long exposures, you must use. Night Photography Settings for Light Streaks: Shutter Speed: 10s to 30s, for motion trails that flow like the Force. Aperture: f/8 to f/11, for balance between light intake and sharpness. ISO: 100-400, depending on ambient light. Too high, and noise will corrupt the image. Tripod: Essential, it is. A Jedi’s hands, steady they may be, but long exposure requires stillness beyond mortal ability. Compatible with all 77mm lenses, this filter is, but beware—an 82mm lens cap, thou wilt require. Such knowledge, crucial it is, lest disappointment consume thee. Verdict: In the ways of photography, a Jedi must always choose his tools wisely. Strong with the Force, this filter is. Recommended, it comes highly.

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.

Out of the gate the first thing you’ll notice is the build quality on this filter. It it feels really solid in your hand, there are no loose parts and has a good weight to it. I like how it has little grip extenders that you can grab a hold of to turn the filter. As the filter does need a little bit of pressure to turn it, it’s nice to have these so your fingers don’t slip. I like how it has hard stops on the ND filter so you don’t accidentally turn it too far, which can mess up your image really quick regardless of what brand filter you’re using.