In the realm of camera gear, there are some truly must have items that will help you out in very specific scenarios. Such one item is a variable neutral density filter. Basically it’s like sunglasses for your camera in laymen’s term. It lets you reduce the exposure without sacrificing on certain key camera settings. For example if it’s a really sunny day and you want to have usable content but because you are using the wide aperture setting, this means you will be overexposed. Or if you are after a certain look for your pictures. Thus meet the K&F Concept Variable NANO ND2-400 filter with 9 stops.

Their logo is “For better Photography” and was founded in 2011, aiming to be a one-stop refined photographic solution provider. They specialize in design, research, manufacturing, and marketing of photographic accessories. They are committed to creating professional and innovative products backed by friendly, responsive service to delight their distinguished customers around the world.


Prices and Availability


It can be had at around $67 from their website or Amazon. Our test sample is the 67mm variant for our lens and K&F carries plenty of the popular lens size to choose from.

*12.07.2021 – Don’t forget to check out the video review as well!*


Presentation, Specification and Visual Inspection


The main highlights are the following:

• Putter Design to Adjust 9 Stops – Designed with a putter, K&F Concept variable ND filter can be adjusted by 9 stops from ND2 to ND400. Each stop is marked on frame conveniently for 360° rotated to adjust the stop, multi-scene application.
• Optical Glass Construction for Clarity – This ND filter is made of Japan-made top optical glass, effectively reduced reflection from the filter itself and glaring, ensuring a high-quality image and does not affect your images in any way.
• Nanotec Coating – Both glass sides of K&F Concept ND filter are multi-coated by the state of art Nanotec coating technology, so the filters are waterproof, oil-proof, and scratch-resistant, protecting your camera lens for an outdoor shooting.
• No Vignetting & Dark Corner – Ultra slim aviation aluminum glass frame with non-slip CNC design, easily install on your camera lens, no vignetting and dark corners even on wide-angle and telephoto lens.

It comes shipped in the K&F classic orange and black combo theme with all of the main features and info printed on the front.

On the back we are informed that it carries 1 year warranty and if you register it this will get extended.

The presentation so far is spot on and we highly appreciate that the filter has its own custom leather pouch with a magnetic flap and a quick access tab.

The ND filter has even its own plastic bag for extra protection.

So here it is the 9 stop variable neutral density filter. It’s entirely made out of ultra slim aviation aluminium with a non-slip CNC design.

The optics are sourced from Japan which reduces reflection from the filter itself and glaring. It has what they call a Nanotec coating which basically makes the filter waterproof, oil-proof, and scratch-resistant. This is very handy for outdoor shooting of course.

To attach it to your lens it’s really easy, just make sure you get one that corresponds to your required diameter (our Nikkor lens are 67mm). Or if you get a step up ring adapter if you want to attach a bigger filter to a smaller diameter lens but that’s another discussion.

The fit and finish is simply perfect. ‘ND’ stand for neutral density as in it should not alter the colours of what you are recordings. Then numbers (2 to 400) refer to how many stops of lights it will cycle through and will darken your exposure. Thus we have 8 markings on the filter aka ‘stops’ plus the 9th per say which is pitch black and it’s not marked.

Now let’s have a look at the variable nature of the filter. We really like that they are not hard stops but progressive and of course they are marked nicely and easy to understand. If you go above the last stop, the image will turn black and it will continue to rotate so no worries that you will force it and break it if there is a lock. So it’s really easy to choose what setting you need especially with the help of that adjustment orange tab. Overall this should cover plenty of most photography needs. The operation is super smooth and thus it’s a joy to operate.


Testing and Feedback


Now here is the ND filter is in action on the Nikon D7000 DSLR camera in quick video so we can see in real time how the filter works.

In a sunny day most people will want to shoot at a wide aperture settings to let the maximum amount of light and thus details to enter per say, but this will make the camera’s histogram scream that we will be overexposed as you saw in the clip. This is how the variable nature of this filter becomes really handy. The same of course applies to pictures where the filter will affect the shutter speed and you can get really creative and experiment to a whole new level.




Overall this variable filter from K&F Concept is a must have tool for any photographer because it will let you overcome certain challenges. Specifically to this one, we can “dial in” the amount of filtration for desired outcome and thus eliminating the need for multiple filters. The built quality is top notch, the mechanism is buttery smooth and thus a joy to operate. The coating gives it the ability to be waterproof and scrats resistant while at the same time offering one extra layer of protection or your lens as well.

The good:

+ Continuously variable with 9 stops
+ Protected against the elements
+ High quality materials and top tier build
+ Will over the needs for most scenarios
+ Excellent presentation and protection
+ Eliminates the need for multiple filters

The bad:

– (None)

Glob3trotters “Must Have!” Award – 5 out of 5


Many thanks to K&F Concept for supplying us with this filter!

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