To all the veteran foldscopers this may sound like nothing, but I am sure excited to present this video to you: https://youtu.be/6UOBy8ztLJQ
It was hard work. My lens was dirty, and the slides were scratched up, despite my best efforts. Then thanks to Laksiyer and EzekielJakub, who suggested phase contrast, I tilted the foldscope. Lo and behold! Little guys, probably 1-2 microns wide, flying through the water droplet, as though they had silvery wings! They look like fairies to me, although I know they’re probably dysentery’s best friend.