This 1- to 8.6-stop, 37mm K&F Concept Blue Multi-Coated ND Filter 37mm 1-8.6 Stopfrom K&F Concept Blue Multi-Coated ND Filter 37mm 1-8.6 Stopis a variable neutral density filter providing an adjustable light reduction of 1 to 8.6 stops. It darkens the entire image evenly, allowing a photograph to be made with a wider aperture or slower shutter speed without overexposing your image. By slowing the exposure time or increasing the aperture, it is possible to control the depth of field and blur movement easily, creating a dynamic look for streams, waterfalls, landscapes, and more. This multi-coated variable neutral density filter does not affect the coloration of the image. The filter's slim design reduces possible vignetting on wide-angle lenses.

Variable 0.3 to 2.6 Optical Density    Multi-Coated    Slim Design    Darkens Entire Image    Greater Control over Exposure Settings    Allows Wider Aperture

Related Questions and Answers

Q: 1. What is the front diameter size of 82mm thread? Does it fit inside Tiltaing Mini Matte Box?

A: The K&F Concept Variable Fader ND2-ND400 Filter (82mm) has an 86mm front diamter. However, please be aware that there are no front threads on filter, therefore you can not connect mattboxes with adapter rings. As for Tilta Tiltaing Mini Matte Box, they only offer adapter rings up to 85mm.

Q: 2. Is there any polarization effect with this filter?

A: The K&F Concept ND2-ND400 Blue Multi-Coated Variable ND Filter (82mm) reduces exposure, but there is no polarization effect.

Q: 3. Are these filters glass or resin?

A: The K&F Concept ND2-ND400 Blue Multi-Coated Variable ND Filter (72mm) is a glass filter.

Q: 4. Is there a lens cap for K&F Concept Variable Fader ND2-ND400 Filter (49mm)?

A: The back of the filter is 49mm but the front is 52mm so you can use this 52mm lens cap on it. https://www.bhphotovideo.com/c/product/807037-REG/Sensei_lc52_52mm_Center_Pinch_Snap_On.html

Q: 5. Does it work in continuous autofocus mode of sony cameras with the Sony FE 28 mm f/2 Lens?

A: If the filter is set to the darker end, that may interfere with the continuous autofocus.

Q: 6. I just bought this filter and I experience something weird. When I turn it over the darker ND dot, the filter seems to go even darker and the photo look like a IR shot (all purple). Yesterday I set the filter at his darker point. I took a photo : f.14, 2.5s, iso 100. Then I turn further the filter and it became darker. So I change the time and I hand to go further as 60sec to get proper expose photo.. but in the viewfinder, it was all purple. Is that normal? I use it on Olympus em10II and 14-42 kit lens

A: The K&F Concept ND2-ND400 Blue Multi-Coated Variable ND Filter (58mm) is only rated to perform properly till 8.6 stops. Going beyond the specified maximum may degrade image quality. Additionally with higher levels of light reduction one runs the risk of IR pollution in the image. As you reduce visible light you are more suspect to this pollution, which could be why you are seeing the strange colors.

Q: 7. Can this be safely used for photographing a Solar Eclipse?

A: I would recommend 17 stops or more for solar eclipse, so I wouldn't recommend the K&F Concept Nano-X Series ND32000 ND Filter (100 x 100mm, 15-Stop) for solar eclipse.

Q: 8. Can I use this to photograph an annular (ring of fire) eclipse?

A: No, the K&F Concept Variable Fader ND2-ND400 Filter (67mm) is not for solar photography and one you can damage one's eyes and possible the camera. Best would be to use one like, https://bhpho.to/45StKoi.

Q: 9. Does anyone know the difference between all the series of ND filters from K&F concepts (ie, nano, B-series, C-series, etc)??

A: The K&F Concept Nano X-Pro Variable filters features double-sided multi-coating and advanced Nano-coating that effectively minimizes reflections and improved image clarity. These are considered the top of their line. The K&F Concept B-Series filters features 8 layers of coating with good optical quality that is suitable for most photography needs. The K&F Concept C-Series are the base level filters with double-sided multilayer blue coating.

Q: 10. does it have front filter threads?

A: The K&F Concept ND8-ND2000 Nano-X Variable ND Filter with Multi-Resistant Coating (77mm) does not have front filter threads.