For the next shutter priority experiment I decided to use this clump of low-growing palm trees as backdrop. I started out with long exposures to see if the occasional people walking past would make a satisfying blur. But in daylight, the long exposure (with shutter priority alone) admitted too much light and washed out everything.
So I gradually shortened the shutter time until I found a balance where I could not let in too much light and still could more-or-less stop motion.
This technique is intended for later use with Mabel Watson Payne under playground conditions.