Just for fun, I took out some expired ( 8 years ) FP4 sheet film that hadn't been stored with any particular care. After developing, there was no general fog ( as seen on the film margins ). However, there was very little evidence of an image....a bit of shadows here and there. Since I am trying sheet film in the 2840 tank ( 11x14 ) for "fun" I am curious if the lack of an image is likely due to the age of the film, or an error in processing. Hence I wonder: What is the effect of age on the emulsion of black and white sheet film? I am aware of the general "fog" caused by cosmic rays, but as noted, the film margins are clear....would aging make the silver emulsion less "sensitive" to light? Thanks for any possible help and opinions.