I just got the NiSi filter holder with a circular polarizer. I did my first shoot, combining that with a 10 stop ND. The images all have a large arcing area of increased density, and above the arc is lower density. Most noticeable in the sky. Unusable.
This is my first experience with a polarizer. In spinning it around, I didn't see any difference in the scene. This was a backlit seascape with lots of glare, so I expected it would be apparent when I turned it to the right position. I'm hoping this is a learning curve issue, but I'm quite disappointed. Any suggestions?