4 x 5.65'' Square Blue Streak Filter Cinema Filter，Compatible with Tilta / SmallRig and Other Matte Box, 4mm Slim/HD Optical Glass/Multi Layer Coating

The 3 stop filter stays on my camera at all times, indoor or outdoor. I film mostly indoors, but the filter allows me to keep a super low aperture (around 1.8) and create a really nice cinematic look. I'd say it's definitely elevated my videos without having to do anything massively technical. The price for 2 of them is hard to beat. I recommend it.

Very exquisitely packaged, luxurious leather pouch containing the soft packing paper-wrapped optical glass. You definitely get what you pay for. The close-up photo doesn't really do justice for the optical filter glass, as I have a colored curtain putting a tinge on that photo. The greenish hue on the product photos was a little concerning too. But the glass itself is properly neutral and clear aside from the evenly spread black specks that blur out into the intentional diffusion effect on photos. It's not for the faint-hearted, just-to-try kind of photography, and won't really work with casual phone-based photographers, as your phone will tend to automatically remove the effect as if there wasn't a filter in first place. It's a proper enthusiast -> professional photographer filter for the intended and desired effect.

mostly shoot with spherical lenses, so thought this might be fun to get those anamorphic style flares from hard light sources. My first impression upon opening are really good. The leather-like pouch feels really nice and has a very useful pull tab that lifts the filter up out of the pouch so you can grab it without getting fingerprints on the faces. I wish more filter pouches used a similar setup. The 4x5.65" filter is a standard in the cinema industry and fits in perfectly with my filter kit and is properly sized for a standard matte box tray. I took a couple photos with my phone that demonstrate how the filter works. As you can see, harder light sources add that traditional blue anamorphic streak across the frame. I feel like blue is very sci-fi and works well in those scenarios, as well as some music videos. It's a bit intense for general use, in my opinion, but for a filter this cheap, it's worth having in my kit for those infrequent times I want to get this specific look. Usually streak filters like this are far more expensive, but this has similar results to those higher priced options. I've been quite happy with my assortment of K&F filters and feel like they punch way above their price point, competing with filters much more expensive. This is yet another perfect example of K&F doing it right and saving me a bunch of money. Would recommend.

At about 4mm thick, with its measurements of 4” x 5.65”, the K&F Concept UV Cinema Filter is a pretty hefty chunk of glass, and with all those coatings, on both sides, a beautiful thing to behold. A UV filter is generally used to, you guessed it, block UV light from a light sensitive material, and very often as inexpensive insurance to protect the front element of expensive lenses. I have a number of K&F Concept filters, most of my lenses live their lives with a K&F protective filter on their front element. I also own some of their other photo/video accessories as well; I consider them a trusted manufacturer. As the seller asserts, their Cinema Filter is sized specifically for Tilta and Smallrig mini matt boxes, although there may be other manufacturers that I’m not aware of. A matt box, that fits onto the front of a lens, is basically used for two purposes, as a filter holder and a lens shade. In the case of the Tilta MB-T15 matt box I use, there are grooves on the leading edge into which the filter slides and is held snuggly in place. Handling the filter takes some care, since it is not enclosed in anything, for example a frame, but is glass from edge to edge. In our case, we keep cotton gloves around for such situations, and use them when handling the filter. Oddly, K&F Concept has always provided a cleaning cloth with every other filter I’ve acquired from them, but not in this case; it would be nice if they did, but I’m not complaining. The filter arrives in retail packaging, with a magnetic closure, that is a storage case unto itself, however the actual filter case, that gives the impression of faux leather, is exceptional. It has a flip open flap with a bright orange nylon strap attached that when pulled, slides the filter up and out, making it convenient to grasp from the edges. The inner lining of the filter case appears to be soft cotton, although I am not certain of that. I ran three tests with the filter: one to check its exposure accuracy, another to check whether it diminishes the sharpness of the transmitted image, and a third to check the effectiveness of its UV blocking. I included results for each. For the exposure and sharpness tests, I photographed the lettering on the back of a box of cake mix, under artificial light. In the case of the exposure test, I simply calculated the exposure with the UV filter applied, and made the exposure. I then removed the filter, and made another exposure without changing the camera settings. I found that the filter has no significant effect on exposure; both exposures were recorded with the histogram in the same range. For the sharpness test, I used the same two images, with and without the filter, and enlarged them 500%. In this case, again, I found that the filter did not diminish sharpness to any significant degree, which is surprising given the thickness of the glass. I provided the pictures and labelled them. To test the filters UV effect, I shot the same outdoor scene, at the same camera settings, with and without the filter. To my eye, it may have reduced UV a tiny bit, but not enough to matter. That said, modern digital sensors, unaltered, record the entire spectrum of visible light, as well as most of the spectrum of infrared and ultraviolet light. In order to record only visible light, manufacturers install what is called an IR Cut Hot Mirror filter over the digital sensor and its Bayer Array of most off-the-shelf digital cameras. Digital cameras sold without this filter are referred to as a “Full Spectrum Camera.” If you’re not sure whether your camera is full spectrum or not, it isn’t; full spectrum cameras produce a result similar to that of infrared film. UV filters are effective when recording on film, but have little added effect when capturing with a digital sensor that already has a UV filter installed by the manufacturer. In the case of my digital imaging, I use UV filters to protect the front element of expensive lenses. And in that respect, the K&F Concept Cinema UV Filter can provide the same protection for expensive cinema lenses without impacting camera settings, in effect providing relatively inexpensive insurance. The physical quality of the K&F Concept ND Cinema Filter, and its coatings, along with the provided case, appear outstanding. I’m looking forward to using the filter in a live shooting situation.

I'm freaking out with the filter. When a light source is placed in front of the lens, incredible flares appear that produce a super professional effect that I love. In addition, the brand is one of my favorites and the quality of the materials is first class. I'm super happy and now my work also has a different touch than the rest

This is a quality black mist filter for your video shoot. It's built nicely, with a good thickness. The glass material feels nice. It fits in my matte box and adds a cinematic bloom to my shot. It's awesome how much one filter can make everything look more dreamlike. Highly recommend!

Always a fan of the K&F quality of filters and matte boxes. I shoot with anamorphic lenses, and still get no vignetting at all. The build quality is awesome and reassuring. Amazon broke one of my filters in shipment, and K&F replaced it so quickly. An awesome experience all-around

Let's just get it out of the way - if you're in the market - buy it. What really stood out to me was the quality of the case. This company knows how to produce a product with the crew in mind.

This filter works flawlessly with my Smallrig mini mattebox and enhances the overall footage from the camera and reduces the amount of work I have to do in post. The filter is very high quality and comes in a very nice travel case that makes it easy to carry with you for on the go shooting. I really appreciate all the effort K&F has put into this filter along with every other filter I've received from them. Personally i like to use this filter when shooting candle lights and porch lights, it gives a great yet subtle effect to the light coming off of the candles and works wonders on neon lights. I will definitely be keeping this in my film bag that I use on set and look forward to buying other filters from K&F to enhance my footage and reduce some work in post.

Super happy with the filter and love the carrying pouch!