This is not thermal imaging, but Schlieren: https://en.wikipedia.org/wiki/Schlieren_photography

interesting even if it required at least 1080p it's super hard to see anything even on a 27" I learned one thing coughing on your hand is the worst, it acts as a launch ramp showering everyone in front of you with falling particles wether you like saturday night live or not they made a few funny sketches related to this and Bernie Sanders who apparently "saw it coming" lol one where an elector coughs in her hands and then try to shake his hand, he says : she did a "cough and shake" another one where he say "I have it on good authority that he's a hand cougher"