torger, i sometimes wish i would have a groundglass that gives me a clear view to focus so i could trust my eyes rather than mathematics. it's a littlebit like flying in the mist only trusting your instruments. (i'm not a pilot though)
but sadly the rm3di is not meant to work this way.
so i have to get familiar with it's physics till i can trust my instruments.
my test shots yesterday showed me that a CoC of 20-25microns will be my safe zone.
i searched for a good place to check different distances and found a parking spot at a sports stadium next to my home.
lens: SK43mm5.6
the app "TrueDoF-Pro" was my buddy. i inserted different blur spot diameters (CoC incl. diffraction as tashley mentioned above): 14 microns, 20microns, 25microns, 28microns, 40microns.
i did a shot at each of these settings set the calculator for hyperfocal distance (f5.6).
i only adjusted the calculated focus distance at each shot and noted the focus distance, as well as the near and far limit of the DoF.
back at home i looked at the results and compared the actual sharpness with the calculation. which setting for BSD would match the real sharpness of the picture?
i ended up with 20microns for "perfect" up to 30microns for "good" sharpness in the predicted areas. (100% view on my monitor)
see also attached one final shot with maximum DoF at f11 2/3 (accepted 28microns and some little diffraction)
focus distance: 7m (100% crop)
near limit: 3,5m (100%crop)
far limit: inf (100%crop)
no sharpening as well as no lcc applied - right out of the box.
i believe i'd be able to print this one at 300ppi 400x600mm with satisfaction...
if i want to go for perfect sharpness 20microns would do the job.
but what if my iphone doesn't hold up battery long enough for a day of shooting? but that's another story
you are right torger, laminated lookup tables are never wasteful