The eyedolls might not even see in the normal spectrum, and not only in the scientific sense. I wouldn't be surprised if, for example, Roy could see into the infrared range, what with the fire theme and all that. And who knows? Maybe some parts of the chapter can see through other people's eyedolls, or something like that. Maybe some can 'see' the flow of air, or see the flow of power around an area. There's just a lot of possibilities we don't know.