Variable neutral density filters are quite a wonderful thing. In theory. They let you adjust your exposure outside of the camera’s own systems as the light on your scene changes. They’re quick and convenient, and expensive if you want a good one. But are they really all that good?
Lok Cheung used variable ND filters during his tenure at Digital Rev. He was typically the one manning the camera filming Kai. But since he’s gone solo, he’s noticed that they’re not really as practical as he’d like. Nor do they really offer the quality that one needs today. In this video, he explains why variable NDs just don’t hold up to the job, and why fixed NDs reign supreme.