This one will be short, cant do much other than posting the chart test
The box comes with cleaning note: Do not use any chemical cleanser
for cleaning, only a soft cotton cloth allowed.
My filter diameter is 58mm, the following test was made on my Canon 450D and kit lens 18-55 IS stopped down to F8.0 for maximum sharpness, shot on a tripod with stabilizer off
Fullsize images to check youself:
Amount of exposure gained with it: the speed went from 1/5 to 1.3 seconds
I'd rate it great
if there is any image degratation, at least it isnt noticeable on this lens I used.
Also it didnt added any tint to the image, a cheapo fotodiox one I use on my S5 IS adds a bit of green to the image