Here's the example: <a href="http://gmanis.smugmug.com/OUTDOORADVENTURES/WATERFALL-GLEN-14/i-G5phRKZ/A" title="Photo & Video Sharing by SmugMug">http://gmanis.smugmug.com/OUTDOORADVENTURES/WATERFALL-GLEN-14/i-G5phRKZ/0/S/Waterfall%20Glen-50-S.jpg" title="Photo & Video Sharing by SmugMug" alt="Photo & Video Sharing by SmugMug"></a> I was using Hoya ND filters 6 stop+3 stop+polarizer. Shot on a GX1 w/ 14-45 with hood. I had shot several other long exposure shots during the day, and in that same position and the majority came out just fine. I was trying out a variety of aperture settings to see the effect on the running water. There were some instances of my accidentally jostling the camera, not sure if this is one of them. The only other explanation was that I maybe caught some reflections between the filters? I did a little googling and couldn't find anything conclusive. Any thoughts?