GND filters FTW!!
I have them and use them, they are awesome. I have 2 and 3 stops and in a lot of cases, I stack them. If I would do it over again, I would have bought 3 and 4 stop filters instead. I also badly need another hard edge GND.
This image is perfect for it, with the flat defined horizon.
Sorry to thread jack. The banding is not really that apparent in the image you posted, only in the 100% crop, for what it's worth.
