Reciprocity failure does vary with films, though for b&w film the tables I use only separate TMax films from all others (TMax films can be exposed for a longer time than others before reciprocity starts to fail - see http://www.largeformatphotography.in...xton-tmax.html - written before Kodak changed the TMax films to their current state but the principles presumably remain the same). However I would think, without really knowing, that bellows factor may or may not also be important. If you're making a 20 or 30 minute exposure it might be insignificant. If you're making a 4 or 5 second exposure, maybe not. Since there seem to be formulas for everything these days there's perhaps a formula for this somewhere.
As reciprocity failure sets in and you increase exposure time with b&w film you'll also increase contrast if you use the same development time as you use without that increase. So if you want a normal negative ("N" in zone system terms) it's necessary to reduce development time to take the contrast increase into account. Some reciprocity tables provide the amount of decrease for varying amounts of exposure increase.
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