Heiiii my first question here!
Right so I'm writing my story and I was going to make the spirit beings just turn invisible (just classic spirit stuff you know) But after reading in this website a fair bit, I prefer it if they just shifted from our visible spectrum to outside of it, and that would be much better because then if they turned completely invisible they wouldn't also be able to see (They can't see you, you can't see them - rule).
Now I dont know much about the history of "ghost hunting" and the equipments+method they've been using so I would preferably make my ghosts in the range of electromagnetic spectrum that famous ghost hunting equipments are able to see.
Also I want a viable way for them from being in our visible light spectrum to outside of it.
So basically I have two questions :
where would my spirits shift themselves in the electromagnetic spectrum to be invisible in our eyes but is visible to famous ghost hunting equipments
how can my spirits achieve this?
Handwaviums can be used a fair bit!