Ghost photo research over half term

From What i have seen of the ghost photos online,  what I have been looking at, the vast majority of them are either black shadows or people in white clothes and have been made to look transparent, the more realistic photos that there are are ghosts that have slight colour to them, rather then being monotone .
So after I return to collage, the photos I am going to produce will be coloured, with the effects we are meant to be adding to make it look old.