Wow, that's impressive.ND8 filter was used. I would have normally used ND16 for smoothing the video out, but the clouds were spotty, in and out that day so I settled on ND8.
My experience so far is if I have either ND8 or ND16 filter on when I take a photo, it will turn out blurry and muddy. I have to swap to the stock DJI UV filter if I plan to take photos.