Mostly a copy from my comment when this was posted elsewhere.
I wish he went a little more into the microdot stuff and tried a little more for getting that small size down. Intelligence agencies aren’t the only ones who use microdots/micro print so there should be information out there.
If you want a more in depth look at just the photography stuff, Alec did quite a deep dive. https://www.youtube.com/playlist?list=PLv0jwu7G_DFV6yW240e6CbiwCLaZ0Z6PV He also made a video about his development process, at least for color, and put that on conextras https://www.youtube.com/watch?v=rW1cg3hDdc4
As a note, youtube seems to have changed something with metadata recently so when lemmy instances not based in the US populate, you only get a generic bit about what youtube is in the local to the instance language, as opposed the the video description. https://yiffit.net/post/11721047
Microdots came from the nazis in WW2, passed to MI5 by the Croatian double agent Duško Popov who btw also tried desperately to warn the US of Pearl Harbor and was the inspiration for James Bond
