The common wisdom is never to buy cheap ND filters! Always Pay Hundreds of Dollars! Or you know, get this one (great so far for video in ridiculous sunlight - ISO 200f/1.7 = crystal clear skies, not a pixel overexposed) and use the money saved to buy another lens or peripherals. Fits perfectly with nice, tight threads, the variable spins smoothly, no green cast or splotchy lines I could see even at 4k zoom, and comes in a cool protective case that fits my pocket like a glove.

I have a tripod and an EF to 4/3 adapter from K&F Concepts and these guys haven't disappointed me yet. Quickly becoming one of my favorite companies.

The thing works great. Smooth adjustment, solid construction. Color looks just right. Cheaper than some competition. Can really control the incoming light without having to change the settings in the camera, so you can play with an aperture of 1.2 outdoors or just fast for run and gun. Here's a trick, get a bigger one and some step down rings so one filter can fit multiple lenses. ;)

I found this filter to work as advertised. I think if you're getting into neutral density photography or video this is a great place to start. I'm now switching to fixed filters and changing them as the light changes instead of using this adjustable one, but I think this is the best place to start

I purchased the K&F Concept 46mm Variable ND prior to my vacation in San Antonio and was super impressed with the performance of this budget filter!

Any aspiring photographer knows how difficult it is to film and shoot in bright sunlight without overexposing everything. This variable ND was the easiest answer to my run and gun film style while I was out shooting my vlog on my vacation.

I definitely recommend this product to people who need lens filters for their shots. Comes in a nice protective case and easily fits in my camera bag!

I am very satisfied with this filter as it was a one time purchase as I also bought the adapter rings to attach it to the camera and the truth is that it is very good. Today I shot outdoors with the filter on and a pass, it's also appreciated that it's variable.
I'm even looking at a polarizer from the same brand.

Knowing you need a neutral density filter and actually using it are two different issues. I'm on the learning curve and the results are mixed because of my mistakes, not the filter. Fit and workmanship are very good, the plastic carrying case makes a robust impression. I would suggest getting an app for your phone to speed up the ND selection process. I used the ND Expert and LEE ProGlass app from the Google Play Store. There are many apps to choose from, but these seemed to be the most user-friendly.

Great product and does what it's supposed to. When shooting with an A7rii and a Tamron 28-75mm G2 there seems to be a bit of vignetting (possibly due to my settings, it may also be an aberration other than vignetting). The variable ND is definitely nice to have and the range is good for most applications. I found it particularly useful in a snowy environment where I wanted to keep the ISO low.

A few criticisms I have that may be unsolvable because 9f is the nature of the article: 1) the lens cap just barely hangs on this filter, possibly a Tamron lens issue, 2) a lens hood not working effectively, the V-ND's bore makes it so that you would THEN put the filter on the cover.

I just had the opportunity to try out my new filter last Saturday. Not only was I happy using it with my Nikon D5200 and 62mm Sigma lens, I also held it hand-held in front of my Sony HX90V's lens while capturing a sunset over the Oquirrah Mountains. Wow! The filter worked well on both cameras! No distortion at all. Love it!

If you are taking photos (or especially videos) outdoors in sunlight, you NEED a variable ND filter.

When shooting at 30fps video, you need to keep your shutter speed at 1/60 (because of the 180 rule) to get natural blur and smoothness. If you want a nice blurred background at f/2.8, even at ISO 100 there's a big chance your image will be horribly exposed. Your only options are to increase the shutter speed (and spoil the natural look with annoying "choppyness") or crank it up to f/16, which will flatten your image and get rid of that blurry background you want!

In addition, there is the variable ND filter. When applied like variable sunglasses, it allows for the amount of light to let through, much like an intimidating bouncer at a nightclub. So just turn the ring on the filter and you can get your shot perfectly!

There were two small things that annoyed me about this particular filter
: 1. The ring has no actual stops, just continuous rotation, so you can't really keep track of the specific amount of light you're letting in.
The filter on my Tamron 28-75 2.8 lens, I cannot put on the lens cap at the same time. Not a deal breaker, but annoying when you want to quickly snap a photo or shoot a video.

But for the price, it's hard to argue that this isn't a great buy.

This is the first time I've used a variable ND filter, so I was a bit skeptical.

I thought this would result in uneven lighting in my image, but to my amazement it is not. I actually have a really cool little product, not sure how it works, but as you rotate the filter the lens gets darker or lighter accordingly and is very consistent all the way.

Didn't notice any color cast or image quality issues. I actually ordered a second one for a different lens I film with.

I only used this filter on video, no stills, so I didn't crop to see if the sharpness decreased, but I didn't notice any decrease in video quality. would buy again.