Transparency note: The product was provided to me free of charge as a sample for evaluation, free from any influence or expectations. My review is based solely on my personal assessment and experience with the product. Review: For those quick readers, I'll give you my review first. Below I'll explain the details of my decision-making process and my impressions of the product. It's not difficult for me to award it 5 stars, because the ND filter meets my expectations perfectly. It functions flawlessly, and the mechanical manufacturing quality is more than convincing, not to mention the useful and practical storage case. One small detail bothers me in the product description: its suitability for 8K videos. What's the point? Is that pure marketing? It seems so. I find this information unnecessary, because one could just as easily say that you can also take photos with it, or that it's also suitable for color reproduction, as well as for black and white. A useless statement. I'm holding a piece of quality craftsmanship in my hands, and I recognize that from the first impression, purely based on the mechanical quality. Wow, what a milled part, the mount ring. No expense was spared on materials, nor on the precision of its workmanship; the fine thread is precisely cut, and of course, there are no manufacturing residues on the filter. The glass, made of high-quality coated optical glass, is absolutely pure and flat. When viewed straight through or at an angle, while rotating, I detect no distortion. This is later confirmed in my photos, and the sharpness of my lens is not negatively affected either. For direct image comparison, I took one picture with the filter and one without it on a tripod, naturally adjusting the exposure. I left the aperture and shutter speed the same, and controlled the light difference using the sensor sensitivity on the ISO control. My premium German full-frame camera offers plenty of scope for this. I see almost no differences; only in contrast, I think I detect a slightly more lifeless image with the filter, slightly less brilliance. Regarding the color tones, I detect a slightly "colder" image, i.e., slightly bluish. I can easily adjust for both in the RAW converter, and I consider these minor influences to be acceptable. Moreover, I only notice them in a direct comparison, which isn't usually possible. K&F Concept delivers truly high quality, as you'd expect. I also really like the filter's grip; even in winter, with cold fingers, I can grip it securely and screw it on without worrying about it slipping. I own a comparable ND filter from a well-known German brand for a smaller filter thread. It's significantly more expensive and only slightly outperforms the image quality of the K&F Concept filter. A direct comparison isn't possible; the lenses are different, hence the different filter diameters. In conclusion, I unreservedly recommend the K&F Concept ND filter. It clearly serves the premium class, or at least the lower premium class, and its quality clearly sets it apart from the cheaper ND filters in the €20-30 range. Thank you for your attention in reading my review. If you'd like, please give me some feedback or a thumbs up, I'd be happy about it.