As with other products from the brand, the KF Concept neutral density filter is manufactured to a high standard and is delivered in a safe and practical case.

Thanks to the special coating of the Nano-X series, there are no unwanted light disturbances in the image when used. In addition, the resistance to scratches increases, which I can really confirm here. Especially when used in nature, I often come into contact with dust, dirt or other obstacles, which, however, have not been able to cause any damage to the filter so far.
The excellent dustproofness and waterproofness of the filter should also be emphasized here!

As expected, the imaging performance of the filter is very good. The aperture levels can be precisely adjusted and are a boon for my 28-75 2.8 lens. This allows longer exposures to be carried out even with open glare and great bokeh can be achieved in bright daylight. Given the sharpness of the image, I couldn't see any differences between images with and without filters. Only in terms of color is there a slight distortion in the direction of warmer shades. But that's nothing that can't be fixed in post-edit.

The filter can also show its strengths in the video sector. Thanks to the continuous adjustment of the aperture levels and the easy and smooth adjustment mechanism, smooth and smooth aperture transitions can be achieved here. This is a great advantage, especially with older cameras!

For such an achievement, every amateur photographer should also be willing to dig a little deeper into their pockets. With this filter, the price of currently around 80€ is definitely worth it! With such filters, it is clear from the outset that the image does not remain undistorted. However, since these changes are really within limits compared to competing products and can be “worked away” afterwards, this is not a point of criticism for me.

So a full 5 stars and a clear purchase recommendation on my part.