I suppose this isn't a fault of the filter itself but it is something that potential buyers should be aware of.My Panasonic Lumix camera has a lens that contracts inside a housing when not in use. I was excited to try out the filter after I received it so I turned on the power to my camera and the lens moved out from its housing. I, then, attached the filter but didn't use the camera immediately so, after 30 seconds, the lens automatically retracted into its housing.Here's the problem -- All other filters I have used have an outer diameter that is the same as the outer diameter of the lenses they fit. That is not the case with this filter -- the outer diameter of the filter is larger than the outer diameter of the lens and smaller than the inner diameter of the housing into which the lens retracts. So, when the lens tried to retract into its housing, it could go only part way before being stopped by the housing. The camera would not turn on again because the lens was not fully retracted into its housing. I had to pry the lens out with a small screwdriver and was, then, able to remove the filter and turn the camera off. Certainly, I didn't want to treat my camera that way but it seemed to be the only altermative; fortunately the camera seems to work as it should after this but the filter is essentially useless with this camera

For the price this is a great nd filter, The only downside is that you get a slight green colour cast but nothing you can’t fix in post production, otherwise great filter.

I purchased the K&F Concept 46mm Variable ND prior to my vacation to San Antonio, and I was super impressed with what this budget filter could do!Any aspiring photographer knows how tough it is to film and take photos in bright sunlight and not have everything over exposed. This variable ND was the easy to answer to my run and gun filming style while I was out and about on my vacation shooting my Vlog.I definitely recommend this product to people who need lens filters for their shoots. Comes in a nice protective case and fits easily in my camera bag!

I never take this off of my Sigma 19mm 2.8. I love this product. I use it every day filling youtube videos and it's perfectly clear as well as great for very sunny days. Shot a full photo shoot with it on and pictures were crystal clear. Amazing

One of the greatest Variable ND filters for its price range.Of course, If you are looking for Zeiss grade accessories, pricewise it will cost you something 10x times more and when talking on such precise and high grade attachments for your lenses, Variable ND filters are not the options - you should have bunch of fixed ND filters, with finest and highest grade glass and coating.This one does same if not more as similar Variable ND filters for $50-70, Slim design, so if you stack it on top of standard protective UV filter, it doesn't generate vignet.Glass is fine and high grade - no significant distortion for most $700-$1200 lenses, which I think is not bad, comparable to lens distortion values itself. Again, if you are such picky for distortions and using Zeiss Otus or even Milvus Primes for over $3000, then you should afford getting fixed ND filters from same Zeiss :)If you have DSLR, your backpack is almost heavy enough, so instead of carrying bunch of fixed ND filters for regular outdoor shootings (and weather is coming up and more bright sunny days we'll have :) ), Variable ND filters are desirable lens attachments and for most of APS-C and Full Frame cameras with sensors common 24 MP sensors, this one is one of the optimal solution.BTW, after great medium range tripod from K&F Concept, this is another camera accessory I've got and I like both - great manufacturing quality, nite and clean, functions as it should be and excellent Price/Quality ratio....

slight green cast. excellent for the money

I bought this for my 7artisans 25mm lens, fits great and allows me to shoot during the day with out blowing out the sky, can be a tad tough to adjust on the fly given it's narrow stature but thats a problem in willing to deal with.. pros out way the cons.

Perfect sunglasses for my lens. Always can rely on this company.

works exactly as expected. great build quality, smooth, easy to use rotating ring that isn't too hard nor too loose

You get color cast, but it's a lot better than Neewer, which came broken