VFFOTO is a smaller manufacturer of photo filters, based in the Czech republic. They mostly specialize on circular filters, but offer also some square ones. They kindly provided me with two filters from their range for a test. The GS ND 1000, which is a 10 stop ND filter, and the GS ND 2000 which is a 11 (!) stop ND filter. Both circular, in the 77mm size.
You can see their products on their official Czech site www.vffoto.com.
I tried both on the Canon 24-70mm F2.8 lens with the Canon 5D mark IV. I also took the same shots with the Formatt Hittech firecrest 10 stop ND filter, for comparison.
VFFOTO GS ND 1000
So let’s first start with the GS ND 1000 filter. This is a 10 stop circular filter. The build quality looks great and it has a very thin profile, to avoid vignetting. Here you can see how it performed compared to the Formatt Hitech firecrest square filter. All photos have the same ISO, aperture and white balance. The only change is the exposure time. The first one, without any filter has an exposure time of 1/30 of a second. The filtered ones are both at 15 seconds.
Here is the first series of photos:
And here a second one, focusing more on the water.
As you can clearly see, there is quite the difference. Where the Formatt Hitech pushes the color quite a lot towards blue/green, the VFFOTO has a much smaller effect and the final color is more towards yellow/purple. The VFFOTO is also much more closer to the no filter exposures. On the other hand, the VFFOTO filter introduces more vignetting, but I presume that is due to the difference in filter types (square filter is bigger, therefore less vignetting).
When looking at sharpness and chromatic aberrations, I can’t really say I seen any difference between the no filter shots and the ones taken through the filters. It looks about the same in all of them.
Overall I think the result from the VFFOTO filter is quite good. It needs a bit of tweaking, as with all ND filters, but it’s quite close to how it should be.
VFFOTO GS ND 2000
This is a more unusual filter. Most companies darkest ND filter is a 10 stop, not a 11 stop one. One tends to stack the filters to get them as dark as this one. As I did not have a second one, I had no filter to compare it with. So what I did, I took the exact same shots as with the 10 stop filters, but of course with double the time. Here you can see both of them, both taken with a 30 second exposure. The results came out very similar to the 10 stop ones.
The color cast, sharpness and chromatic aberrations look all the same as with the 10 stop VFFOTO GS ND1000 filter. It is really impressive how much you can stretch the time with a filter like this. From 1/30th of a second, to full 30 seconds, without the need to change any other settings. It makes for some buttery smooth photos. And to show you that, I tried one at full 4 minutes. To be exact, I did it twice, one at ISO 100 and one at ISO 400 to get a +2 EV exposure. And here you can see the final blend. It was not a very colorful evening, but it does show how nice and smooth everything is.
Overall, both filters create some very nice results, and I can’t wait to use the more, once the weather get a bit better.