More hardware today: cut up and soldered one and a half more reels of LEDs. Looks like I’ll have less horizontal resolution than I originally planned, it’s just too much work *and* I don’t want to have to buy another strip (not to mention wear another half a kilo of battery.)
One thing I did confirm was that tapping in power every six strips or so got around the voltage drop that had been causing a steady drop-off of all but the red channel after four or five strips.
The warnings on the LiPo batteries (DO NOT LOOK AT BATTERY PACK SIDEWAYS, IT WILL EXPLODE AND TAKE A LIMB WITH IT!) are starting to scare me, I might go with two NiMh packs instead of one big LiPo.