I'm starting learning compositing with the usual cliche, a UFO flypast. All going well so far, sorted 3d tracking, colour correction and masking, but one thing I'd like to do is use the flaring of the cheap camera footage as a brightness modifier for the UFO layer.
As you can see there is lots of vertical hilight noise from the cheap sensor, so I assume I need to make some sort of luminance mask from the background footage and precomp this with the UFO layers, but I've been playing with this for a day or so and frankly, I've hit a wall. I know I could ignore this, as it's unlikely anyone normal would notice, but I'd like to learn how to do this just for my own satisfaction.
Any hints, help, or links to online tutorials would be welcome. Thanks in advance