I’m not a big fan of filters, especially considering how many effects are available these days in photo editing programs. In the wrong hands, filters can produce gimmicky, predictable results and stifle creativity. But for others, they can stir the imagination and encourage experimentation. I found that to be true with the K&F motion blur super speed effect filter. I tried to avoid the typical, knee jerk motion blur effects, and I was quite happy with the results—see photos (additionally edited). The filter rotates on the threaded ring that mounts to the camera lens allowing it to easily be set at any angle. The 58mm filter weighs 2.4 ounces and measures more than a half inch at its thickest point. It’s some pretty serious glass. Included are three microfiber cleaning cloths and a padded plastic case. There’s a two-year warranty. Extended warranty registration and additional product information is available at the company Web site.

I have been using this rather unique filter for some time now. It was a little odd to use at first, but figuring out the right lens and composition to use is half of the fun. My preferred lens to use was my 8-18 f2.8-4 on my G9. I found that using the long end of the lens gave me an equivalent focal length of 36mm on full frame, and allowed the context of the scene to determine the placement of the lens effect. One thing that caught me off guard was the thickness of the filter. But at least you know your front element of your lens is well protected with this filter. I just enjoy the process of coming up with different compositions with this filter setup. Once you nail it, the results are great. I tend to keep this filter on my 8-18 just in case I come across the right scenario to take some fun pictures. This is a great tool for a seasoned pro, or just someone like me learning how to frame a scene properly. This will make you a better photographer the more you use it.

Very artsy looking photos thanks to this filter. Its very easy to use and is clear with good optics. I used this in the studio with colored gels, it provided visually striking results

This is a useful filter for creating motion blur effects. I've also been able to create an interesting Fata Morgana effect and a wet/puddle water effect on street surfaces. This filter takes quite a bit of effort to get good results but they are worth the time. The light transmission is good and the non effect area is sharp. The actual build of the filter is very good and it looks like it will hold up well as long as the glass is protracted. The plastic storage box is good but because of the weight of the filter I plan to keep it in the case and keep the case in the box. This is a filter that will spark creativity and help you get a new perspective on common scenes.

This motion blur filter is a fun, creative tool for photographers looking to add in-camera effects without post-processing. It creates a directional blur that works well for stylized portraits, action shots, or anything where you want to suggest motion or a dreamlike atmosphere.

The glass is clear, and the build quality feels premium. It threads cleanly onto the lens and comes with a cleaning cloth. It takes some experimentation to get the right angle and look, but that’s part of the fun.

It’s a niche tool, not something you’ll use daily, but for artistic shots, it adds an exciting layer of creativity.

A solid pick for experimental creators or professionals looking to expand their visual toolkit.

I had soooo much fun using this filter and seeing what cool creations I could make. You know when you get tired of taking the same old photos the same old way? Well this will spark those creative juices in you. I love the effects it delivers. Go ahead and get yours, I bet you will feel the same way.

Before all the post processing special effects, people use filters like this for that unique look. I have a lot of fun playing with this. The photos look more natural, not artificial. The filter is thick and heavy on my Olympus mirrorless camera. But it is bearable. Overall, a great filter for that unique look.

I bought it more for experimentation than for real need, but I must say that the K&F Concept medium linear prism filter pleasantly surprised me, essentially for its very precise and complete package.
If you like playing with light, creating dreamy or cinematic effects directly in-camera without having to spend too much time in post-production, this filter is for you.

The effect it produces is unique: the lights trail horizontally, creating a kind of "trail" that can be very evocative, especially when working in urban nighttime environments, with point lights, signs, or headlights.

It has that something that immediately gives character to the shot or video, and allows you to achieve a creative mood right from the moment you shoot, without digital artifice.
For those interested in fashion portraiture, it's definitely recommended (although I'd suggest adding a couple of alternative filters I've seen sold by the same manufacturer, such as the "Triangular Prism" and "Central Hexagonal Effect," which I think can be very satisfying for studio photography).

The build quality is acceptable; the glass is optically clear and shows—it doesn't produce any strange aberrations or color casts.
The metal ring is sturdy and screws easily onto the lens, in this case a 58mm (I got it for a 100mm macro f/2.8).
The package also includes three cleaning cloths, which are always useful when working with filters, especially if you're doing street photography or shooting outdoors.

One small detail to keep in mind: the effect is directional, and the filter can be rotated, so you'll want to carefully study the effect you want to achieve so you can direct it at the right time and pose.

Overall, for €35 (which It's very little), if you like to experiment and think outside the box, it's a nice addition to the kit. It's not a filter you'll use all the time, obviously, but when you take it out... it does its job.