I've had and still have many K&F products, so I'm not surprised when it's this good. It always is. The packaging. The carrying case. Both look like they hold fine jewelry. Sharp-looking, with sturdy construction, and the result is absolutely amazing. Cuts down on all the harsh glare/reflection, and smoothes everything over. And so much better, being variable, than having to try multiple filters to get the desired effect. Love just being able to adjust it to where I want it. And, it works like magic. Thank you, K&F Concept

Pros:

1) Retains image sharpness
2) Warmer color cast (which I prefer)
3) Higher contrast than Freewell
4) Larger range ND range than Freewell
5) Build quality better than Freewell
6) Better carrying case than Freewell

Cons:

1) Each ND stop does not have a hard stop or even a numeric indicator so you're not sure if you are on ND 8 or ND 16. This can be a con for some but for my use it is not a big deal as I primarily shoot video and use a monitor to gauge my exposure and just rotate the ND until exposure is correct.

2) Filter does not have a hard stop when it reaches 400 ND and you can keep rotating it till you get the X pattern.

I'm comparing this filter to Freewell ND mist version since that seems to be the most popular ND filter being used especially in the wedding videographer circles.

In terms of overall build quality I want to say the K&F filter definitely feels a lot better. Even the overall packaging makes you feel like you bought a premium product. I really like the rubberized coating they use. It feels very premium and it has a good weight to it. The anodized orange indicator is nice and allows you to adjust the ND stop easily. The case that comes with K&F's filter is much more useable and compact compared to the bulky plastic cases that freewell gives. (There was a time that
freewell's filters wouldn't even fit their case if you installed the magnetic cap which was a huge oversight on their part although I do wish K&F had a magnetic cap as well since those are the best IMO)
I am primarily a video shooter and I was hoping that the filters would have similar color casts but unfortunately they don't. It's not hard to fix this in post but still would have been nice if they did match as I have multiple cameras. I do however prefer K&F's color cast as I tend to like warmer images. I also like the halation on this filter more than I do the freewell. If you look at the image where I put the two side by side the K&F is more contrasty and the light spread is kept where it should be and not across the entire image like how the freewell does it. This looks a lot more natural to my eyes. In terms of sharpness I could not see a distinct difference between the two. Both look excellent.
Biggest gripe that I see other people having is the fact that there is no indicators on the filter aside from the first ND2 and ND400. The rest of the stops are indicated by dots. I don't know why manufacturers create an excellent product and then do these kinds of small short cuts. Although for me in real world use this probably wouldn't affect me, it did make testing the two different filters a pain. This is the reason why I have only included one comparison shot because I could only test the ND2 on both filters as that is the only two ranges that are clearly marked on both filters.

At the end of the day in spite of some of it's shortcomings the filter does do an excellent job of what it is supposed to do. Cut light without messing with overall image sharpness or colors and give it that nice "cinematic" glow and I honestly think it does it better than Freewell. Thumbs up from me and will be using it at my next paid gig.

You will not find a single negative thing to say about these.
Perfection as usual from k and f

Very practical as you have multiple ND filters in one, no need to carry many to be replacing until you get the right density. No vignetting at f2.8 on my Sigma 24*70 APS-C. Camera is Sony VG-30

Everything about this was well made and executed. I love that the filter is so easily adjustable. I've been using a square slide in filter mount for years and while it works great, it's kind of a pain to have to carry a stack of filters and swap them out in the field.
The downside here is it's a fixed diameter, but I typically only use it for landscapes on my go to landscape lens so not really a big deal for what I do. I also really like the case it came in. It's a nice hard sided two-tone leather like case with a magnet closure. It's easy to slide into a bag or pocket but sturdy enough to keep it protected.
Adjustment of the ND stops is incredibly easy with the thumb bar. Overall, really great adjustable ND filter!

This thing is beautifully made and beautifully machined. All of the rotation are smooth and fluid. The low profile brass ring screws on the lens barrel perfectly.

This is an interesting diffusion filter which gives you a variable neutral density while at the same time giving you 1/4 soft effect. The result is gorgeous. I prefer the optical effects to the digital ones and it certainly saves time when you were doing video.

The glasses optically perfect and the neutral density gives me the option to lower down the shutter speed to get some smoother shots on things like moving waves. The diffusion effect is subtle but it softens the edges of the shadows just enough to give you a nice pleasing effect. It also works great on skin.

I was able to enhance this sunset shot in camera with this filter without having to do any digital processing. The shadows were harsh and the sun was a little too bright. This soften the light and at the same time allowed me to smooth out the water with a longer exposure.

If you're like me, you can't get enough dark, misty, ethereal and foreboding atmospherics in your photos. Well, that's the look I'm going for when I use this black diffusion mist 1/4 filter from K&F Concept. The Variable ND2-400 filter comes along for the ride but the Black Diffusion Mist filter is clearly...err...'not so clearly'....star of the show.

I already had the K&F Black Mist 1/8 filter, which adds more of a dreamy and slightly otherworldly effect to photos. I shoot a lot of photos at night in cities, and the 1/8 filter is perfect for that scenario. Even at night, cities are bright but if you're shooting without this type of ambient light the 1/4 filter is the club you want to pull out of your bag. In some ways, both filters create an effect that evokes analog cameras. One of my favorite subjects is Southern Nevada and you can get some really cool images with these filters. I've used the 1/8 for shots in Las Vegas (spoiler alert: lots of lights there) but I'm looking forward to using the 1/4 to shoot in the desert or some of the more remote towns between there and Reno.

At one point, photographers would try all sorts of tricks to soften up their images. Rumor has it that 'Penthouse' publisher/photographer Bob Guccione would slather Vaseline on the lens to get the look--'The Gooch' thought he was a much better photographer than he really was but his obsession with soft focus imagery really differentiated his publication from the more lurid competition no matter how he went about getting the effect. Less messy photographers would go with black pantyhose over the lens.

I don't consider myself a serious photographer--I'm primarily a writer that started taking photos and videos to accompany content. I'm trying to learn more about photography and at some point when I have more time I'd like to get more into the artistic side of images. For now, however, I'm pretty content getting interesting photos/videos with my Nikon Z-30. I've started messing with filters to try some different effects.

As for these K&F filters, they're a perfect fit for my 50-250mm telephoto zoom lens. They apparently have little black particles inside the filter to get the black mist effect--in fact, you can see them if you look closely which you will because your first reaction is that it's dirty. I can't give you an expert analysis on the build quality, but the frame is anodized aluminum and that's a pretty burly metal. The glass has 28 layer multilevel coating and it comes with a nice storage case. I have enjoyed using my 1/8 K&F filter and I'm looking forward to putting the 1/4 through its paces. Highly recommended!

I own Tiffen's Black Promist 1/8 and 1 so I know of their quality. I thought i'd try this new filter from K&F and I am pleasantly surprised! Very good quality and definitely an alternative of the Pro Mist that people should consider. it renders wonderful images.

MRC coating on this is quite poor; got lots of flare and haze from reflections, which are especially problematic with a mist filter; you can't push the contrast up the way you usually would, as it ruins the mist effect. Look at the top right on my attached photo, at the top of the tree.

Additionally, the mist effect is different than other black mist filters I've used, and not in a good way. The suspended particles are a lot larger, even in the 1/4 filter, and are easily visible to the eye. In practice, this resulted in a less appealing bloom effect than the Hoya and Tiffen filters I've used. I suspect the larger particles are causing a lot more refraction, which is what's causing the haze.

For the price, they're not unusable, but I would recommend paying more for one from Tiffen or Hoya.
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