I absolutely love this filter. I took it to the ND filter battleground, the Bonneville salt flats of Utah. It was a very bright sunny day. Below are the stats of the attached pic. Straight out of camera with only a exposure bump up in post to make it brighter. I shot dark to save the highlights.

Camera: Canon 7D
Lens: Tamron 85MM f1.8
F-Stop: 1.8
Shutter: 1/8000
ISO: 200
White Balance: 5100K
ND Filter: Max

I'm set this filter to it's max setting to see if there was any issues to be found and they are miniscule. The chromatic shift of yellow tint is easily fixed in post and is much better than the harsh magenta/green shift of some cheaper filters. There is a slight addition to vignetting, but easily fixed as well. The clarity and contrast is minimally affected without much loss of sharpness. Nothing that a little bump in post can't rectify as well. The harsh light didn't affect contrast too much when shooting towards the sun either.
What impressed me the most about this filter is the build quality. It is solid and the rotating action is very smooth and holds its place. Even with me moving up and down it stayed where I had placed it. It really is a solid smooth action.
I really like this filter and it's an awesome piece of kit to have to get to the those low apertures.

Tiene una construcción de gran calidad, se ajusta perfecto al lente, es muy liviano y sus cristales son excelentes. Cumple con todo lo prometido.

I’ve been a fan of K&F Filters and accessories for some time now, and have come to appreciate the consistency and the quality of the brand. The majority of my lenses live their lives with K&F UV protective filters on their front element.

Like many others, as the caliber of mobile phone imagery and videography have improved to levels of near professional quality, I’ve begun to concentrate more energy into taking advantage of those attributes, not to mention the portability. Both in videography and photography, whether using a full-size camera or a high-end mobile phone, I consider both ND and CPL filters essential.

In hand, the K&F Concepts combination Variable ND2-32 and CPL filter gives the impression of quality. Between its matt black finish, the gold adjusting levers and the reflection of the multi-coatings, it’s also an impressive filter. In fact, I own a couple K&F variable ND filters in other sizes, although this is the only one that includes the CPL.

A variable ND filter works in a similar manner to a CPL, that is, there are two-rings, one that attaches it to a lens and the other that is turned to control the degree of transmission from more or less light, effectively allowing control of exposure. In this case, it’s the CPL that attaches to the front of the lens, with the ND component in front of that. In order to control each independently, the CPL has more resistance when being adjusted than does the variable ND component, which is adjusted using the gold levers on the side of the filter. That being the case, the user first adjusts the CPL to the desired position, then adjusts the variable ND to facilitate the desired exposure; it’s a system that is thoughtfully designed.

A ND filter, whether variable or not, is used to reduce the amount of light reaching a light sensitive material. In videography, it is generally used in order to follow the convention of a low ISO and a low shutter speed or a specific shutter angle. In still photography, it's used to allow for the use of a wider aperture in bright light situations or to reduce shutter speed for some desired effect. In either case, the benefit of the K&F Variable ND filter component is that the transitions between minimum and maximum light reduction are not stepped, but infinitely variable between its 2 - 5 stop range. In other words, one can set their camera to the desired settings, then rotate the light reducing transition ring to achieve the desired matching exposure.

A CPL Filter is used to reduce or eliminate certain non-specular reflections and also to saturate colors, for example a blue sky. Generally, a CPL itself requires a certain amount of exposure compensation, in my experience somewhere between 1.5 – 2.0 stops, because they also add neutral density when placed in front of a lens. Interestingly, and baffling, is that K&F has compensated for the ND effect of the CPL in their calculation of the variable ND component of the filter; when the ND is adjusted to its minimum variance, that is ND 2 (or .3), only one stop of exposure is reduced, not one stop plus the exposure reducing effect of the CPL.

Testing the filter for any reduction in image sharpness not only revealed none, but the example with the filter in front of the lens actually looks a hair sharper to my eye; each image has been enlarged to 505%.

The K&F Concept Variable ND plus CPL Filter comes from a trusted manufacturer, is high quality in fabrication, light transmission, and materials, and is essentially two filters commonly used together in one efficacious assembly. In other words, this single assembly allows for some control over distracting reflections, can enhance color saturation and allows for precise control of exposure settings, in what can otherwise be uncontrollable circumstances.

The K&F Concepts Variable ND plus CPL Filter is delivered with a hard plastic case and a nice cleaning cloth.

I have owned the KF Concept VND and CPL for one year and ten months. I noticed that the stacked filter in between them was giving an issue with their being weird what looked like bubbles. I contacted their support warranty team and without any questions, they asked if I would like a new one free of charge.
I recommend this company in general I have many of their products from lens filters to tripods. All the lens filters come with a 2-year manufacturer warranty combined with an affordable price, making this a way better item!

I have had a few K&F filters over the years...and I have found it to be hit and miss...but there are a lot of variables involved and I still go back to them.
This one is a hit.
I have included two images...involving some greens and blues...one is maximum ND and one is minimum ND...only the shutter speed was adjusted for exposure...and both images look natural and clean...good details in the pines.
I like the build quality, it has a nice heft to it.

So...why not 5 stars then? Just one niggle. I appreciate the adjustment grip on the sides...both sides...nice. But I think it needs to be dampened a bit more...just seems to slide too easily, and with the two grips protruding (you can take them off)...the filter could be moved without my even being aware.
It's a small niggle...I will live with happily...not a big deal...just not perfect...few things are.

Nice bit of kit...big thumbs up!!

I am an amateur photographer and in no way my opinion is professional. I have always been amazed by what filters can add to your photography game but the need to change between filters plus cost made trying them a challenge.

This filter seems to answer these concerns, it is multiple filters in one so no need to swap filters, just rotate to your choice.

The quality of the pictures is hard to judge since it is winter time and no sun light to filter, saying that however I don’t see any black crosses or distortions.

As for the price, it is reasonable. Almost the price of one filter.

I only started using filters about a year and a half ago, so my experience is limited. However for me, I believe this to be a quality filter. I did have to use a step down ring to attach to the lens I was using. To use this filter, the ND portion is adjusted with the tiny knobs and there are markings on the filter ring to guide you. The Polarizing filter is adjusted by moving the ring closest to your lens in a circular manner.

Here’s what I liked about the filter:
1. The housing is a metal housing and the moving parts glide easily. The filter is built well.
2. It comes with it’s own storage case which has a foam cutout to perfectly protect the filter.
3. The glass appears to me to be good quality.
4. I did not notice any vignetting when using.
5. Image sharpness was not significantly degraded.

The filter also came with a sealed microfiber cleaning cloth.

I like that you are basically getting two filters in one purchase and the filter is a good value. Five stars.

Combining an ND filter and a Circular Polarizer in one filter is such a helpful filter, there's almost no reason to remove this from my lens, unless I am shooting indoors. Having both in one filter and being able to dial both in separately is such a good tool and accessory, it is really amazing for using when shooting outdoors in bright sunlight, for being able to lower the f-stop to get my aperture low and get those wonderfully creamy blurry backgrounds, and also dialing in the reflections off of the water, or enhancing the skies. This filter is quite a bit larger than most, and is definitely not a small thin filter, but the glass is great quality, and the threads are machined perfectly. I have no complaints about this filter at all and am really happy I decided to order it. It will get a lot of use from now on.

I am using this filter for outside shots on an IR converted Canon 40D with an internal 720nm filter. The CPL helps to make the open sky even darker, and the ND filter gives me the flexibility to do some cool shallow depth of field shots when close to wide open in sunlight. I had to use a 52mm to 55mm step-up converter to fit the Canon EF 50mm 1.8 II (nifty fifty) lens, but this setup matches the barrel diameter perfectly so it's not unwieldly.

I’m really impressed with these filters. There’s a variable ND plus CPL filter and it works great. There’s no weird color cast or anything like that. The image is super clean. Also, I like the design with the two bolts that don’t allow the filter to over-rotate creating the dreaded “X” pattern that some variable NDs get. Also, it makes it so easy to know when you’re at the lowest setting and the highest setting. But most importantly, I just really like the image quality coming from these filters. Highly recommended.