What does a photographer do, when they're looking to create a look, for a photo session, and that look requires multiple angles of capture.. but you only have 1 ND filter for one of your 82mm lenses?

... get another ND filter, of course.

Yeah yeah.. I know, it was a corny lead in (but a very real problem we ran into a few months ago).

The fact is, I honestly don't know what happened to K&F in the last couple of years, but they went from a sort of 'Oh.. another filter manufacturer' to a 'Wow... that's a fantastic result!! Who makes that filter??'

This filter is NO exception to the above.

ND filters are often a double edged sword for photographers.. They work, and they do what you want.. kind of.

They tend to add a color shift to your images, add distortion if you have cheap glass, and can often push your camera to the point that you have to do manual shutter control... thereby requiring you to do trial and error photos.

On top of that, when you use an ND filter, especially for very long exposures, you're going to be fighting the light, as it were. As the light of the day changes, so will your exposures... and while you're doing a lot of trial and error, a 5 min exposure at noon, won't give you the same result at 5pm, so it's not like you can 'set it and forget it', so to speak.

Then, when you add the word 'Variable' to the equation.. that's when things tend to get even stranger. As you adjust the ND level, you will often find yourself experiencing strange banding, sudden lurches in exposure changes as you adjust the ring, AND that doesn't even consider the fact that so many ND filters have very loose adjustment rings, that (I kid you not) can sometimes change their setting, with a strong breeze.

This filter... WOW.. I can honestly say, I have none of the above issues. There IS still a slight color shift, but its even, and doesn't change as you increase or decrease the ND level. Also, the levels are smooth, and clear, and there seems to be no distortion... which is extremely shocking to me.

Also.. there is NO rattle or looseness in the ring, which makes me happier than it should, to be perfectly honest.

The adjustment 'putter' makes it easy to adjust without getting your fingers on the edges of the lens (makes it easier to adjust, if you need to dial up or dial back, based on light... this is especially helpful with video).

I really only have 3 complaints, and they're extremely minor.

1.) As with any filter, I'd really like to see K&F either add a magnetic mount option, or include a filter tool to make it easier to twist on or off. I know someone will say that the 'putter' makes it easier to do, but I don't trust applying pressure to a free floating multi-part filter.

2.) The case it comes in, is different from their other Nano-X series cases. It's more of a pleather type, whereas some of the others are sort of suede/denim style.

3.) Threaded front element. I know some people will say 'you NEVER stack filters!!!'. Yeah, well, there are a large number of photographers that do it.. if you don't want to, fine.. but don't argue against potential functionality.

Its works amazingly well, and doesn't interfere with the image I'm trying to capture, so the above 'complaints' are more of a wishlist, than anything else.

Definitely recommended.

I bought this for my sony lens and it worked perfectly! Great for day time long exposure shots. Quality was great and the threads were perfect! Also nice that it added some protection to my lens.

I am new to this brand of lens filters but I'm happy with the image quality and fit on my lens. It's easy to adjust and stays put on the setting you've selected while you photograph. I was able to get some great waterfall pics and a sunset pic using this filter and you can't tell the difference between this and my expensive brand name ND lens filter when reviewing the images.

Ever since I started reviewing the K&F filters I have become a major fan of the company. The quality of the filters and the construction are excellent. The glass has been of extraordinary optical clarity and the brass rings are precisely machined. I’ve never had any problems with cross threading or stripping. The filters go on very smoothly and come off just as smoothly.

They are very of all filters have just enough friction to stay where you put them but turn buttery smooth on the camera so you won’t have to worry about moving your camera on the tripod. they are just a really pleasure to use. This per tick Euler filter has appropriate markings around the rim to let you know which stop you’re setting is at and it has a little tab to make turning the filter easier. It’s a very low profile and should not cause any interference with your image I.e. no vignetting.

Back in the old days a problem with variable neutral density filters was you would get this artifact of the two polarized plates crisscrossing and you would get these optical “X” artifacts in your image. I believe the newer ones used a spiral circular polarization and this allows you to have an artifact free image.

This filter does exactly what it supposed to do which is to darken your image to allow for longer exposures or just cut out extreme light and glare on a very bright day.

One thing I notice about this filter is that his measurements are extremely accurate. If you said it for four stops and then take it off and lower your camera for stops down, the lighting is going to appear identical although there will be a little more glare without the filter because the polarization also cuts the glare.

Another optically perfect excellent filter from K&F.

This is a lens I never had before. Seems so dark. But no....when I took shots, they were defined better, clarity was excellent and the only difference was a slight color change that was easily fixable. It fit on my Canon lens fine. It comes in a decent if cheapo fake leather pouch, but I have it in my camera kit, in its own place. When I get to African again, can't wait to try this out on landscapes and safaris early in the morning.

I was pretty late to jump onto the ND filter bandwagon because I am old photographer and still to this day shoot film 90% of the time. With film, we learned how to make camera adjustments to do the same thing you would achieve with these filters. well, nearly the same thing.... I am shocked at how much simpler it is to work in harsh light, and to capture long timed exposures with using this Variable ND filter!

One question I had was "will this work with film or pretty much just for digital?" and I am happy to say that it does come in handy for film as well, but I do believe that its greatest strength is in digital photography.
This filter is one of the best quality built filters I have ever come across, its silky smooth to rotate, but has enough friction that it stays right where you set it at and does not slip to another adjustment. I could not believe my eyes, but it also acts as a mild Polarizer filter too. I was able to shoot in very harsh and bright sunlight and using the darkest setting have a exposure that was nearly 2 minutes long and was able to see right through the reflection of the water. I have never been able to do that before!

I really love the little orange nubbin that they call a "putter" on this filter too. it just makes adjusting it so much easier. I am totally sold on the use of ND filters now, and with this one being variable adjusting it is the only one i will ever need! very happy with it!

This filter is perfect for when you want shoot with a wide open aperture in bright daylight. Well built and easy to use.

The K&F Concept 77mm Variable ND Lens Filter ND3-ND1000 (1.5-10 Stops), Putter Adjustable HD Neutral Density Filter with 28 Multi-Layer Coatings for Camera Lens:

This is a variable neutral density filter of the finest quality with little to no color shift. it covers 10 stops of adjustment and is perfect for video or very shallow depth of field photography. Everything about this filter is top quality. from the packaging to the leather filter holder. There is a Pulltab on the side to eject the filter and a finger nub on the filter itself to rotate the ND adjustment. This is a very fine piece of glass that you don't need to think twice about putting in front of your best lenses. In the past I've had problem with harsh color shift with other vari NDs. So far this seems great. I will report back if I find anything I didn't see in my first impressions. This is a premium vari-ND that I recommend to pro photographers and videographers. Very high quality materials and very well made. Nice glass.

This is a nice filter. I've been very impressed so far with the quality of K&F. It's obvious they work with photographers to get them exactly what they need - not just scientists and marketing experts. It is well thought out and functions beautifully.

I'm not seeing any distortion from the use of this filter.

I see minor color shift (yellow/green). It looks slightly better than my Tiffen viariable of the same power. It is easily neutralized in post production (or through custom white balance).

The knob/handle is fantastic for easily adjusting the ND filter. I really like having the grip. The additional grip is also a nice addition.

The case is attractive and functions well.

I do wish it had a hard "stop" on it for the minimum and maximum settings. It'll keep on spinning around and around. Not a huge deal, but it would be a nice and welcome addition.

Overall, this is a great filter.

This is a really nice filter, definitely worth getting especially if you don't already have any ND filters. I'm using it on the stock lens that came with my Canon M50 and it is very fun to play with. The lens itself looks and feels high quality, and is easy to adjust. The case it comes with is nice but rather large.