Lighting glitter/confetti/mylar (5 replies)
Think of the mylar as little mirrors -- if a mirror was dangling on a string, what sort of light would create a reflection in it from the perspective of the camera? Or think of the mylar as a spinning mirror ball -- you'll note that often those are lit from four directions at least and what you see kicking off of the mirror ball are the two more frontal lights, the other two are reflecting backwards. Angle of incident equals angle of reflection, so a light next to the lens would be reflected when the mylar was facing the lens flatly. A myler rotated 45 degrees would reflect a light that was 90 degrees to the lens, etc.
The lights being reflected don't have to be super bright either since the mylar is so shiny. A small hard light would create more of a point source kick and a soft light would reflect over the whole face of the mylar, though if the mylar pieces are small, even a small hard light would reflect over most of the surface at the reflective angle.
Also how close the reflected light is to the falling mylar would affect how bright it looks. If there were layers and layers of mylar pieces falling in depth, some close to the performer and some close to the lens, then the fall-off would be more noticeable and the foreground reflections would be much brighter than the deeper reflections. But due to inverse square law, if your lights being reflected are farther behind the camera, the fall-off wouldn't be so fast.
All of this is to say that it is a bit hit or miss, you have to play around a bit with the lights you want to get reflected in the mylar pieces. I might start with three small lights, frontal, and closer to right-angle or 3/4 frontal, or just two 3/4 frontal, etc.
You could drop small pieces of front projection material and light it with a minimal source at the camera. I say front projection material but I guess you could use what is used on a security uniform. I have done a fake moon and other things in this way.
I think you will need quite a few buckets of silver and gold glitter to get this right and of course a large broom. Very time consuming but should be worth it.
Brilliant, thanks everybody.
David, that breakdown is very helpful and front projection is a neat way of going about it. Definitely feeling a bit more comfortable going into shooting. Excited to experiment and see what results I get.
The director might like to bear in mind that the compression algorithms for digital media such as TV and DVDs may easily lead to on-screen artifacts such as blotching and pixelation. Digital compression does not like frame-to-frame changes right across the entire image as the data required will exceed what the system is designed to cope with.