An ultra compact lens weighs only 145g, with a wide field-of-view of 100˚ on full-frame. 8 out of the lens’s 9 glass elements are specialized, and a linear STM motor provides fast and precise autofocusing. Every unforgettable moment can be captured with exceptional quality. Broaden and deepen your photographic world with the AF 18mm F2.8 FE – an innovative wide-angle AF lens that offers new possibilities.


First impressions are very good I love it when you purchase a product and it comes in some nice packaging, it comes in a nice solid box, inside the box you get the filter in its circular plastic case.

presentation and packaging it up there with the big boys.


Practical use:

the weather has been rubbish since getting this filter and I wanted to review for my blog and well as YouTube video, but I took it out with me to a few locations to test the claims made,

Gear used was a Sony a7Rii and A7iii the reason for using two different cameras is that I fund a 42MP camera will how more problem if there are any, I used  the new Samyang 18mm f2.8 which has a very wide field of view it’s a 58mm thread lens so I got a 77mm filter and got an adaptor this saves you some money in the long run.


with all this being said the one thing I was worried about was the fact that the 18mm was so wide and with the adaptor I thought I might get some vignetting, GOOD NEWS due to the slim profile of the filter  being 7mm  I had no such problem so for all you landscape photographers out there this is perfect,


Colour cast is no existent with this filter which is a big problem with the cheaper versions and some more expensive ones I have used.

No “X” cross on images.
This was something I really wanted to test, I compared it to two other filters I have, A Hoya and a no name brand filter, the cheaper filter has the horrid cross as soon as you hit ND 20 there about.

Now the Hoya which is twice the cost of this shows the cross effect at about 50% of its ND capabilities which is very disappointing and again a reason I do not use it anymore.

the big question is does the K@F filter show the cross effect, the simple answer is NO it has no sign at all, again the image above is this filter at its maximum ND capability ND128


Something else I noticed was the sharpness in my images was not affected at all using this filter,


Is it waterproof and oil resistant yes, I tested that over the sink and was perfectly fine the water just beads off.

I have not tried the scratch test as I find time will tell more than getting a knife out to it?


if I am to be honest I really can not find one for this filter, I could be picky and ask for a cleaning cloth with it but to be honest and I am very honest with my reviews, what K&F advertise is exactly what you get with the extra benefit of the filter not affecting sharpness.


Final conclusion if you’re after a filter for landscape and even videography I would give the K&F Concept  Variable ND Filter a 10/10 . For the price you pay you could expect to pay 3 time the amount for other named brand from the same thing.

Hope you found this useful.

images from top to bottom all with the filter at their maximum equal ND capacity

MIddle: Zomei
Bottom: K&F Concept



→ Small and light weight

→ wide field of view

→ No Dark cross when using

→ Slim profile

Great value for money


→ No cleaning cloth