Hoya PRO ND 1000 55 mm

I use this filter to shot water falls and rapids...And it's great... I also ordered the 58mm

I have both the 4 stop and the 10 stop ProND filters. I have not used them extensively, but find their quality very good and have no evidence of the color shifts that I've seen with some other ND filters. If you're looking for circular ND filters, these are a great choice.

This filter works very well. The light reduction is about 9.6 stops, which is very close to the advertised 10 stops. It has a slight green cast, but the cast seems to be pretty uniform across the frame, so it's easily corrected in software. This almost neutral color rendition is much better than another ND filter I've tried.

I was very happy with the results when I used this in Bryce Canyon NP photographing the Mossy Cave Trail Cascade in the mid day sun, it worked perfectly, allowing me to use a long exposure to blur the water. However, in my recent attempts in using it, I am getting a magenta cast in the center of the image. Thoughts on why this is happening now? The attached image is straight from the camera...

Amazing ND filter, no added color tint here, best of its kind