Long exposures: I have done seconds to many seconds with 400b and 3000b with no apparent problems. My attitude on that is kind of blase, though; if I don't get what I want I just dial in a longer exposure and reshoot. Matching reciprocities could be computed, in principle. Anyway I think I've done ~8 sec exposures with 3000b (pinhole!) and also some rather long, multisecond exposures with the fp100c, no problems. I don't recall trying fp100b over more than a second or two but certainly ~ 1 second should be no problem. Short answer: no guarantees, but I think you will be very pleasantly surprised.