Gainer "...Due to the fact that the factor 1.62 works for these diffeent films of different manufacturers, it is my opinion that it will work for any current emulsion to acceptable accuracy. That is to say that I expect it to be within the spread among readings of indicated exposure made by a number of proficient photographers of the same scene. If this is the case, all one needs to know is the reciprocity correction to one indicated exposure to find the correction for any other indicated exposure"

This is tremendously helpful. I'd like to chime in my vote of thanks for sharing your work also Mr Gainer.

I do have one question, and pls accept my apologies if the implication is already clear.
From your statement we can assume the 1.62 to be a constant factor for all current emulsions (then it would make sense for it to apply to FP4 and 320TXP OK). I guess if we wished to establish the reciprocity correction for different emulsions from those established by Howard Bond, we would need to do our own experimentation?