Picked this up to mount on my iPhone filter adapter. While this is part of the K&F entry-level line of filters, it surpasses the quality of some more expensive filters. K&F is my first choice when looking at filters these days. They have products at just about every price point and each provides a high level of value in its performance class. This filter is no exception and is an excellent entry-level ND filter for the price.

Can't be that much of a shock that bigger glass = more money, unlike buying garments. Using auto iso during indoor lighting, it ranges between iso 12800 to iso 5000. There is vignetting, but normal under the circumstance. Hence the reason for having variable lens. The lens behave like polarized sunglasses where you get different shade when you tip it sideway. Lastly, lens hood won't work when you install this filter.

I own several of K&F's filters and none have ever disappointed me. This one is no exception. The filter is knurled both front and back of the front element ring. this makes installation and operation easy. The front filter turns smoothly yet has enough resistance to make it hold it's position reliably.

The 43mm ND filter came in a typical filter case along with three pieces of microfiber cloth. I also own a 49mm ND filter from K&F which has been working well.

The filter looks well made. Clear markings on the filter and easy to rotate and set it to 1-5 stops for reduced light. It is easy to mount the filter onto the lens and remove it. One thing that was mentioned in the description but I missed to read it is that this 43mm filter needs a 46mm filter cap. I do not own a 46mm lens cap and so will have to buy one.

I have shot quite a few images with this filter, the light gathered by the lens is reduced as the filter ring is rotated to a higher stop. The filter ring does not rotate beyond the min or max stops and so this resolves the X cross problem. I will use this filter for long exposures when it gets a little warmer where I live.

This filter is not water repellent or scratch resistant and not slim. Filter quality is good, happy with the results so far. Price is ok at $29.99.

I shoot a lot of video and needed an 82mm ND filter, so decided to order this variable ND filter and I am glad I did. This is really nicely made, and is so easy to change levels of filtering, from lighter to darker by just turning it a little bit or a lot. It's a very visible change that you can easily see in the glass. The threads are perfect, and I had no problems screwing this onto the front of my lens or removing it. Image quality was excellent as well, with no visible distortion in my images whatsoever. This is a really nice filter.

Nothing but high quality from K&F Concept. Their products deliver every time. This filter is no exception. ND2-32 is a daily driver, for the in-between shooting after blue hour and before golden hour. Adjust really easy and there are no X's in the images.

I wish all VNDs were at least at this level of quality.
Little to no color cast, hard stops, clearly marked and almost low profile. This hits all the marks I need and is going to be permanently on my 50mm f/0.95 lens.

This is a review of a 77mm K&F Concept Nano-K Series ND2-32.

First impressions are that this is a very well-made filter for the price. The body is machined from aluminum, with a matte anodized finish. The threaded rear ring is nicely knurled. The rotating ring has very fine knurling on the front edge. There are varying sized dots on the edge indicating the number of stops (1-5) of exposure reduction. Numbers would be a little nicer, but the dots are not hard to figure out.

The rotating front element is larger in diameter than the rear. This should minimize any vignetting with wide-angle lenses. However, if you expect to stack filters on top of this, be aware that the thread diameters are different. On the 77mm version, the diameter of the front threads is 82mm.

The filter threads into the lens smoothly with no signs of binding as you often see with inexpensive aluminum framed filters. Once mounted, the front ring rotates smoothly, with hard-stops at 1 and 5 stop positions. The total rotation from the minimum to maximum position is a bit less than ¼ turn.

The 1 to 5 stop range is good for bright conditions where you need a slower shutter speed to sync with fill flash, or a wider aperture to better separate the subject from the background. If you need super long exposures for super silky water effects, K&F makes a variable 2-9 stop version, as well as 16 and 20 stop fixed ND filters.

The stop marks on the filter rim appear to be pretty accurate. Using aperture-priority mode, the shutter speeds were very close to the expected progression. Starting at the 5-stop setting, the speeds were 1/8, 1/20, 1/40, 1/80 and 1/160. And removing the filter yielded a speed of 1/320.

Coloration is the downfall of many ND filters. Through a DSLR viewfinder, this filter seems to add a subtle greenish-yellow cast. Surprisingly, in my test images this coloration is visible only at the lower density settings. By the 3 stop mark, the color balance is quite neutral. Overall, not a bad performance.