Going to buy ND Filters. Was going to buy N4 N8 N16.
How do you set up camera after ? Is auto best ?

Hi, Its better to use manual settings, basically keep your ISO as low as possible and when you use the filters you can get your shutter speed down, also depends on what FPS your shooting in.

Use the general rule of shutter speeds, 1/50 for 25fps, 1/60 for 30fps and so on. The nominator value is the frame rate times two. You can still see the EV value, try to keep it between -0.7 and +0.7 and perhaps turn on the overexposure warning to notice blown out areas.

Dont use auto!!!! Dial that shiznit in and make it exactly what you want.  That's the beauty of using filters!!!

Manual shutter should be 2x times your fps setting then your aim is to have EV close to 0 when you hold up your drone towards the horizon. This can be accomplished by trying different ND filters.

I found This tread has a couple of good videos giving examples of how to use the filters.