I am starting to play with f/stop timing for print exposure in my darkroom. I ha ve read several papers on the subject and like the way it works. I have noticed in some tables of f/stop increments that, as expected, +1 stop is a doubling of the time. For instance base exposure of 16 sec +1 stop = +16 sec. So far so good . BUT for +1/2 stop the increment is +6.6 seconds. I am surprised it is not 8 se c which would be 1/2 of the full stop increment.
SO, there must be something I do not understand and perhaps a formula for figuri ng out fractional f/stop increments both up and down (+ and -).This, I am sure w ill help me understand the non linear nature of these f/stop increments.
My goal is to make my own tables of f/stop increments for the range of exposures I use, and understand the process.Can any of our large format math wizards help me?