Yeah I get that you cranked the exposure. But the shadows on the tree trunks suggest point source. But maybe not. If it was a diffused source then reflections are out and the objects are generating their own light...but then what, fairies?
I am leaning toward fireflies.
I went out last night at 7:35 and they were already in the trees, I counted over 50 distinct lights. . . it was two hours earlier than we'd seen them, but it was colder. Maybe their settling in for the night is a function of temperature. What I found most interesting is the duration of any particular flash was quite long last night. I timed three at over 45 seconds each. I've never heard of firefly bioluminescence lasting more than a about ten seconds for any particular insect before turning off and having to have a recovery time before going back on. 45 seconds seems to me to be a very long time.
They seemed to be brighter than the previous night. . . but that's a subjective observation as there is no real way to measure among the nights except my impressions.
I wonder if such high tree lights were not the origination of the myth of fairies?