Hey Flare....good insight!Originally posted by Flare
IR filters blocks out most visible light, but allows IR radiation to go through. But since to allow for use on SLR, which wouldn't allow the user to see anything through the view finder if the filter blocks out all the visible light, some of these filters allows some red light to get through. But digital camera with an LCD screen or an EVF, will not have problems with IR filter that blocks out all lightas we can still see the IR image on the LCD or EVF. And since our eyes can't see IR, the image taken may yield very interesting results!
There are two different types (tho you can't really class electromagnetic wave distinctively) of IR, Near IR and Far IR.
Near and Far are in respect to the position of the wavelength in respect to that of visible light on the electromagnetic spectrum. The Far IR is the one used for thermal imaging. Digital cams sees the Near IR, and does not really photography Heat, thus it will not work at night unless you shoot a beam of IR to be reflected (night shot and nightframe of Sony's F707) or you are trying to take pictures of something that is emmiting IR (maybe a big bonfire? just maybe)