I been using my 3 filters from SRP religiously and just cant really figure out whens the proper time to use them. I have the ND8 CP and non CP I also have the ND 16 CP. One bad thing I will say about them. I noticed during the post is will give a black ring around the image. Looks very unprofessional and I have to zoom or scale the image to blend the faint black ring. Going on to my question. I noticed sometimes it would be too bright that even the ND 8 did not work properly and I will have a poor image quality whether its a jello effect, noise or rolling shutter. The sad part is I will never notice when I'm out and flying. But, during post thats when it gives me a headache. What are your guys tips and advice to using ND 8 and ND 16 filters?