Originally Posted by
francongphotography
I've taken quite a lot of shots with my ND filters, mainly for landscapes.. The IQ, do indeed degrade when I stack 3 filters for that 13 stops of slower exposure..but when I use only one filter at a time, the filter only affects the IQ by a little. Not as much as when I stack up the filters..just really lacked sharpness and the images appear really soft..kinda goes along with that dreamy water effect though :)
But I had to say, these square filters are really convenient...as I just need to buy different thread sizes for my lenses and screw on the filter holder and be ready for the shot. Saving loads of money from buying different sizes of circular filters for my lenses.