I set the aperture high and ISO low in an attempt to keep from overexposing the trails from
each explosion, then used a tripod and remote release in BULB mode, opening the shutter when
the rocket headed up, and closing it when I'd accumulated enough blooms for a good composition.

I had rented a Canon f/2.8 IS for the long weekend and may have forgotten to turn
off the IS because each streak seems to have high-frequency waviness to it.