For some of the sounds, I did the same as you... played a YouTube video and captured the wav on my phone, then airdrop to the iMac Pro. By the way, the sound associated with the two scenes that go to white (maximum exposure) is from my bathroom vent fan!
I'm going to do more of this sound stuff. There are some servo motor sounds I'd like to capture from the auto folding rear seats in my Ford Explorer, and the linear actuator in my bed. Maybe I can use them in my next movie.My previous hobby prior to drones was restoring antique radios from the mid 1930's to 1940. I have sold off much of my collection except for a few of the more valuable pieces. Anyway, the simulated "fusion" or "reactor" is simply an aluminum tube shield from a radio. I put a bottom plug in it, double sided taped it on the battery, and dropped in a Firehouse drone strobe light. Then filmed that sequence in my shop at night using red heat lamps for special effects lighting and smoke generated from a burning Kleenex. Steven Spielberg would be proud! Obviously it was supposed to simulate a battery modification capable of 1.21 "Jiga" watts, or in this case, Amp-Hrs. My wife was the camera lady. Fun!
