I got my B&W 10 stop ND filter in today. I thought those shots of rivers and lakes with super glassy water were amazing. Being a wakeboarder and VERY newbie barefooter, I know glassy water is very rare, so there had to be a trick. The “trick” is using a 10 stop ND filter. This allows you to take pictures with VERY slow shutter speeds. I’m talking like 3,5,10,20,30 second shutter speeds. Without the filter, even if you crank up the f/stop, it will still be too bright during the day. With this dark filter on, it requires more light to correctly expose.