This 77mm Nano-X Pro Series ND Filter from K&F Concept is a premium quality neutral density filter that darkens the entire image area for both still image and video applications by 10 stops. Increasing neutral density offers finer control in available shutter speeds or aperture settings. Using a longer shutter speed makes it possible to increase blur to convey a sense of movement, as when shooting running water. Increased density also makes it possible to shoot using wider lens apertures, helping to isolate a subject from the background and increasing bokeh. This level of image control can help to create more cinematic effects in low to bright light.

The filter is made from optical glass that features 36 layers of nano-coating for reduced lens glare, providing reflectivity as low as 0.15% for ultra-high light transmittance. Each optical surface also resists water, oil, dust, fingerprints, and scratches, making it ideal for use in harsh environments, and also easy to clean. The slim brass filter ring is designed for use with wide-angles lenses without vignetting.

Solid Neutral Density Filter    3.0 Filter Factor, +10 Stop    Darkens Entire Image Area    Allows Long Shutter Speed, Wide Aperture    Optical Glass Construction    CNC-Machined Slim Brass Filter Ring    36-Layer Nano-Coating    Waterproof, Anti-Smudge, Anti-Scratch    Leather Storage Case

• High-quality optical glass
• 36-layer nano-filter multi-coating reduces lens flare and ghosting
• Low 0.15% reflectivity ensures ultra-high light transmittance with no color cast
• Resistance coating is anti-scratch, waterproof, oilproof, dustproof, and suitable for harsh environments and locations
• Slim, lightweight brass filter ring avoids vignetting with wide-angle lenses

Related Questions and Answers

Q: 1. Hi there Is this ND compatible to use with Sony Fe 400/2.8—i.e. internally? Thanks

A: No, the B+W 40.5mm XS-Pro Digital ND Vario MRC-Nano Filter would not be compatible for use with the Sony FE 400mm f/2.8 GM OSS Lens. While the Sony FE 400mm f/2.8 GM OSS Lens does use 40.5mm filters, the B+W 40.5mm XS-Pro Digital ND Vario MRC-Nano Filter would be too thick for usage in the drop-in filter holder.

Q: 2. Can anyone explain the dot markings to stops on this filter?

A: I had this same question and decided to run some tests (using my Nikon D810). I did this inside with the lighting (more or less) constant. I ran three sets of tests: 1) in manual mode with auto ISO, I noted the ISO without the filter and with the filter positioned at each of the ten different dot makings; 2) In manual mode (and constant ISO) I set the aperture to zero out the meter without the filter and at each of the dot markings; and 3) In aperture priority mode, I noted the shutter speed without the filter and at each of the dot markings. The results varied somewhat depending on the test. Reported below is the average of the three methods. The first dot corresponded to 1.0 stops, second dot to 1.1 stops, third dot to 1.4 stops, fourth dot to 1.8 stops, fifth dot to 2.2 stops, sixth dot to 2.5 stops, seventh dot to 2.8 stops, eighth dot to 3.2 stops, ninth dot to 3.7 stops, and tenth dot to 4.1 stops. So, as others have said, the dots are just a guide.

Q: 3. Does anyone know if my Nikon 24-70mm f2.8 VR lens hood works with this filter attached?

A: NO,...the lens shade will not work....I just test fitted it....the filter id wide than the hood opening. I have the AF-S NIKKOR 24-70mm f/2.8E ED VR lens. On a Nikon D810.https://a href= http://www.bhphotovideo.com/c/product/1175033-REG/nikon_af_s_nikkor_24_70mm_f_2_8e.html target= _blank www.bhphotovideo.com/c/product/1175033-REG/nikon_af_s_nikkor_24_70mm_f_2_8e.html/a

Q: 4. Hello. I purchased this filter but I am having difficulty working out the stop values for each dotted marker increment on the outside ring? I assume the first dot is 1 stop and last dot is 5 stops. If you divide the rest by 1/3 stop or 1/2 stop, then it does not work out mathematically. Any tips or manuals for this lens?

A: Unfortunately, this is typical of most variable neutral density filters across the spectrum. The markings between the minimum and maximum do not accurately indicate a precise number of stops, and even brands than mark them with ND factors miss the mark significantly; some brands are off by 1/3~2/3 stops with engraved filter factors. While I am not familiar with the physics and/or engineering reason for this, a commonly accepted technique is to adjust the camera settings first and then dial in the VND filter factor. This might be hard/impractical with longer shutter speeds though, so preemptive testing might be necessary.

Q: 5. Can someone explain the markings on the filter? Thanks

A: The markings are 1/2 stop increments. This helps you determine the proper exposure.

Q: 6. The filter factor is not listed here. On the K&F website, it is listed as 1.3 stops. You're welcome?

A: The K&F Concept Nano-X Pro High Definition Circular Polarizing Filter (${Size}) does have a filter factor of 1.3 stops.

Q: 7. Can this filter fit the Sony 10-18mm wide-angle lens?

A: That is a very wide angle lens and I would suspect a vignette problem. The answer to that would be to buy a step-up ring and use the 77mm version of filter. Now you have a filter that will adapt to any lens you might have with the appropriate step-up ring. By the way, the 77mm and is often on sale for less than the 62mm.

Q: 8. Does this filter vignette with a Canon 10-22 lens at 10mm on crop sensor camera?

A: A super-wide such as this lens will inherently vignette. The filter is a high level of quality and does not add any noticeable distortion to photos.

Q: 9. anybody using this filter? Have you had any problems?

A: I've had it for a few months. Bought it because the Bower 95mm was just awful.... you get what you pay for! Personally, I've noticed no X pattern on this filter at all -- even at its highest level of filtering. I've not noticed too much of a color shift either....

Q: 10. I have a Sony A7S with Sony FE PZ 28-135mm f/4 G OSS Lens and shoot video. I like the flexibility of the variable ND filter especially as I often don't have time to change filters. Is this the best for exteriors?Thanks Andrew

A: It's that or a mattbox with ND, especially for shooting Log2 or Log3 at 1600 or 3200iso.