>>2842380No, I'm just not sure where you pulled "base ISO of 400" from. Base ISO on digital cameras has almost always been very near to 100, and has stayed there, through many years and many improvements to both dynamic range and color.
When Sony gave us 14-stop DR cameras, up from 11, they didn't do it by dropping down from the standard ISO of 100. The base ISO stayed 100 (or close to it) because a lower base ISO doesn't have anything to do with dynamic range or color.
The base is 100 (or sometimes 160, or 200, and sometimes 64, or 50) because that's where people want it to be. ISO 100 was pretty standard for film, so they carried it over. It's a good speed for daylight stuff, and much lower wouldn't be very useful for anyone not doing long exposures, in which case something less like 50 or 25 wouldn't make much of a difference, and they'd rather just use a 10 stop ND filter.
