I tried this using a flir one on my iPhone. https://youtu.be/IMxZQ922rLs https://youtu.be/IMxZQ922rLs Sorry, it sounds like a really good idea, but it just do

I tried this using a flir one on my iPhone. https://youtu.be/IMxZQ922rLs https://youtu.be/IMxZQ922rLs Sorry, it sounds like a really good idea, but it just doesn't work very well in practise. The users fingers don't sit on the keys long enough to transfer enough heat to last. Just use a standard video camera if this is your thing.