What is ND filter (neutral density)?
Neutral density (ND) filters reduce light entering the drone camera, allowing slower shutter speeds for cinematic motion blur in bright daylight. Common values: ND8, ND16, ND32, ND64.
Aerial video benefits from a shutter speed roughly 2x the framerate (24fps → 1/50 shutter, 30fps → 1/60, 60fps → 1/120) — known as the 180° shutter rule. In bright daylight at low ISO and a fixed aperture (which most consumer drones have), achieving these slow shutter speeds is impossible without an ND filter.
ND filters reduce light by a fixed amount: • ND4 — 2 stops, overcast or shaded conditions • ND8 — 3 stops, bright but not direct sun • ND16 — 4 stops, full sun on subject • ND32 — 5 stops, very bright (snow, beach, midday) • ND64 — 6 stops, extreme bright
Most pilots carry an ND8/16/32 set. Variable ND filters (single filter with an adjustable density ring) trade flexibility for slight image degradation.
What this means for pilots
If you shoot video, get an ND filter set. Without one, you're stuck with high shutter speeds that produce stuttery motion in panning shots. For stills, ND filters matter less since you can adjust ISO/aperture. PolarPro, Freewell, and DJI's own filters are common brands.
FAQ
Do I need ND filters for stills?
Usually no — adjust ISO or aperture instead. Long-exposure stills (water blur, light trails) benefit from ND.
ND8 or ND16 — which to start with?
ND16 covers 'full sun' conditions, which is the most common daytime shooting environment.
Variable ND or fixed?
Fixed for image quality. Variable for convenience. Working pros usually carry both.
Related terms
FAA regulations change. Verify current rules at faa.gov/uas before relying on this article for flight planning. Altoa is not the FAA.