I have used ND filters for a number of flights but not typically the kind of very low level flying near close up things I expect to do with my Avata. For those of you that have spent any time using ND filters to get a slower shutter speed while filming with the Avata, do you find the typical 2x FPS to be a reasonable goal. Do you get there with an 8x on a bright day when shooting 60fps (something like 1/120 shutter?). I'm awaiting a very grey day but will begin to play with my new ND filters but thought I'd see what experience others have had.