Ernest, I can only try to provide help in a general way as I don't know what is special about the F100 in terms of it handling IR sensitive film. The window in the back should provide no major problem but to be safe you could tape it up with some IR opaque tape - lacking that, aluminum foil cut a bit larger than the window opening and taped in place should work fine. As to IR frame counter - I doubt it has it but a sure sign that a camera does have this method of controlling how much film travels through the camera per frame is the lack of the ubiquitous sprockets in the camera body next to the film aperture gate. These steps really only take care of making sure the film will not get fogged by unexpected sources of IR - now, how will you use the Kodak film in the camera? I have the dubious "honor" (seldom recognized however!) of having introduced the method of placing a visually opaque but IR transparent filter "between the film rails" in an SLR camera so that the viewing system might still be used to frame a subject in motion. (in particular such subjects 'cause otherwise you place the camera on a tripod!) - of course if you use a separate finder or a TLR or rangefinder camera that is a moot point. most people use a Wratten #25 or #29 red filter over the lens of SLRs to make near IR photographs. The Kodak instruction sheet is quite helpful here in terms of giving you good starting points for exposure index selection with various filters. The filters over camera lens make scenes look red but viewing system is still useful. andy
