I have only started buying K&F filters in the last 3 years, but there is absolutely nothing negative to say about them. I love the filters from K&F.

This type of specialty filter is a bit pricey so I usually buy the size that fits my largest lens. That jacks the price up even more, but I use adapters to enable using them on smaller lenses.

Super happy that I found this and saved money since I was originally going to buy the tiffen filter. It’s worked well for me and I’m super happy with the results it provides!

As most K&F products, the build quality of this filter is quite nice. The threads are smooth, filter ring is powder coated and then optics... well, hard to say they're clear or anything since they're a diffusion/soft filter, but the picture quality is still quite good. More on that later.

The filter comes in a circular filter case that is one of the neatest filter cases I've seen! If they don't sell those as products yet, they honestly could! There are raised partial circles that allow you to place all sized filters in the case, unlike most with a foam cutout (which, admittedly offers more padding). It would be nice for the filter case to have a small sticker on it to indicate what is basically on the box--"NANO series 52mm MRC Black Diffusion 1/4" in my case. In fact the outer box has that listed a few different times, including twice on the sticker label... one on the case would be even better.

The optics look like a clear glass with a bunch of small grey dirt specks. That is the intended design. The effect it creates is a soft diffuse glow; a bloom effect. The contrast is lowered when using this black diffusion filter and overall it looks like a similar effect to a soft filter. The sharpness at the point of focus isn't too affected though, so it can still be used in portraiture as well as in other creative photography. Light sources will bloom when looking through this filter. I find the 1/4 strength to still be quite useful while the 1/2 an 1 may be more niche.

I got this to use with my Fuji xf 35mmf1.4 (55mm thread) I love the vintage look I can achieve with it. Think smoky barroom, portraits behind a candle, any photo where you might want a little extra glow from the lights. I have a much more expensive 72mm pro mist filter, but this one gives me just the look I want when combined with the magic of the xf 35 1.4. Recommended

Very good!

While they are not B&W or even Tiffen, I do like K&F Concept filters. Their filters tend to be well made, have a minimum of distortion and colorization especially considering their reasonable price. The 52mm Nano-X Black Soft Filter is another example of a well made, inexpensive filter.

Keep in mind that this is a special effects filter. It won’t be much value in normal, everyday photography. It is a Diffusion Effect filter. These filters were very popular in Hollywood films especially in the 1940s and 1950s. The were used for reducing blemishes and wrinkles on actor’s faces (especially on women) and for creating glowing effects. However, if you need or want these kinds of effects in your images, the K&F Concept 52mm Nano-X Black Soft Filter will do the job at a reasonable cost.

I ordered this for my husband and he loves this filter. It has taken some steps out of his editing process. He likes this filter, because it does so much during photo shoots that he doesn’t have to waste time fixing small imperfections during editing. He says he noticed a big difference in the quality of his photos pre editing. The filter is thin and fits well on his camera. The quality of this filter isn’t bad. It seems to be holding up well and not showing signs of wear and tear. Great product!

K&F contacted me to test the new Black Mist filter.
It is a filter designed for videos and to give a "vintage" touch to the final result.
In short: beautiful result even for photography. It is a useful filter for portraits or for landscape or storytelling reportage. You do not lose sharpness and you get a much less "shot" light that also expands in the shaded area.
It is a filter to be used in photography with large apertures and which "tells" an atmosphere.

But let's start from the beginning.
Packaging / handling: In addition to the plastic box, the filter is inserted in a very resistant and protective snap-on case. The filter is screw-type (rightly because it was created for videomakers and in any case up to a diameter of 82). I would have preferred a cardboard box. But the case that you can see in the photo (the round one) is very useful and sturdy. The filter is resistant and fits well to all the lenses to which I have mounted it.

Technical review:
It has no dominant details, so it leaves the colors similar to the photo taken without a filter. Great!
It does not lose light, there is no need to increase the ISO when it is mounted. Great!
The sharpness in the details (and here comes the beauty) remains almost unchanged. You DO NOT lose sharpness in the areas in focus even if I would not use it in ultra-defined landscape photography, but for a storytelling, outdoor or portrait set absolutely yes.
Autofocus is unaffected by the filter, at least not on the Nikon D750 with fixed lenses.

Usage / Effect: it is a filter that gives a “glow” effect to photos, very particular especially for videos and for portraits in harsh light or backlight.
The highlights are dimmed but without becoming dull, moreover the light "enters" the shadows, giving a very soft "glow" effect. Great for portraits or to give a more dreamy atmosphere, it removes clarity from the image in high contrast areas.

In the photos you can see a couple of unfiltered / filtered comparisons, two portrait photos set and what comes to you.

Result in short: it is a filter that you do not think can enter your kit, but when it does it has such a particular result that you would try it in any situation. A must try!

Very good product

Let's start at the beginning. What does a "crap filter" do? It ensures that lights get a "blurr effect". In German the lights look a bit hazy. This can create a really cool look in film productions, but is also really useful for photos for portraits etc. For example, a chain of lights in the background of the model or similar

Autofocus works perfectly with the Sony A7 Mark 2 and the Kito lens.

What I find absolutely awesome is the "packaging" or where the filter is stored. Nothing wobbles here! This is rock solid and can even be used for other filter sizes.

Oh: Despite the filter, the lens hood and the protective cap for the lens fit without any problems.

Processing as always top! no plastic ;-)