10/4 planes gives 100fps on the active3 spiral demo on 3 64x64 panels, or
1.2 megapixels/second. And to my eye, there's no brightness shimmer.
All the below settings "look good" to my eye, higher FPS ones tend to look
better to a camera. In "10/4" mode with my camera at 100FPS it still looks
solid but because the beat frequency between the dither pattern and the
shutter is pretty pronounced I can see it shift between the sub-frames.
There's still some brightness variation between modes, with more planes
being a little brighter than fewer planes.
10/0: 50fps
10/2: 72fps
10/4: 100fps
8/0: 92fps
8/2: 109fps
8/4: 134fps
5/0: 135fps
5/2: 153fps
5/4: 210fps
