A few months back I read a pretty favorable review for the FOTGA 46mm variable ND filter on CheesyCam.com. In fact the author was so pleased with the results that he even stated that he was going to buy the 77mm version. Though I couldn’t find a decent review at the time, having been in the market for a cheap variable ND filter and the fact the FOTGA 77mm variable ND filter was only about 20 USD (from eBay) I reckoned it wasn’t that much of a risk. So, now that I’ve had the filter in bag for a few months how does the FOTGA 77mm stack up?
On first inspection of the FOTGA 77mm I was quite pleased with the build quality. The case is pretty ordinary but provides adequate protection and opens and closes relatively easily. The outer rings are made of a sturdy metal and labelled in visible white print. They rotate relatively smoothly but are not so loose that you need to worry about slipping even if you were to run around with your camera. The filter also screws in smoothly.
My only disappointment was that the lenses don’t appear to made of glass. My best guess would be a type of plastic, which isn’t really surprising given the price.
Having watched reviews on other cheap filters I was expecting to see some color shift (probably towards a blue or purple color). This didn’t bother me too much though as I always shoot RAW and can change my white balance after the fact. As expected the FOTGA 77mm does have some color shift but the nice surprise was that it actually added a bit of a warmish tint which some might find pleasing.
If there is anywhere the FOTGA 77mm breaks down it would be in it’s performance, but don’t stop reading yet though the results might surprise you.
In terms of pure light stopping power the FOTGA 77mm cuts out 2-stops of lights on it’s minimum setting plus nearly another 7-stops (minus 9 total) at it’s maximum setting. At minus 2-stops of light vignetting or other aberrations are well controlled and virtually unnoticeable.
From minus 3-5 vignetting is noticeable in the bottom left and top right corners but certainly still useable.
At minus 6-7-stops the vignetting is pronounced. again in the bottom left and top right corners, but might be useable for low key shots.
At minus 8-stops the vignetting is severe and at minus 9-stops the filter is unusable.
One thing I still haven’t tested is the sharpness. I have noticed some degradation but over all I’ve been satisfied with the performance of the filter.
Let’s be honest the FOTGA 77mm variable ND filter is not a high-end filter. If you’re shooting a full frame camera with any quality lens and looking for edge-to-edge quality this filter is probably not for you (if this sounds like you this video from Learning DSLR Video is a must see). However, if you’re like me and only use a ND filter on occasion, to give you a few extra stops to slow your shutter speed down to get that smooth water effect or when working with flash outside, then the FOTGA is a reasonable option. It’s not the best thing going but in terms of dollar value, it’s a solid performer.
For those interested all test shoots were done handheld on a Canon 550D. The lens was an EFS 10-22mm 3.5-4.5 shot at f7.1/ISO 1600. Each time I turned the ND filter I would go until I dropped 1 stop of light in the in camera meter and then I brought the exposure back up by adjusting shutter speed.