Cinefoil is a thick, matte black aluminium foil (substantially heavier than kitchen grade foil) which can be shaped into any form to allow you to flag off part of your light source to avoid unwanted spill.
It's a simple idea but a fantastic time-saver when you don't have sufficient flags/nets/scrims, or enough time to throw up a c-stand, or even if you simply want to wrap a light fixture with it to create a sort of snoot, to your desired dimension. And it's sturdy enough to be completely reusable, so a 7 meter roll will go a very long way!
