Rich's Tongfamily

Well, while scanners can handle up to 3200dpi, there are very few prints that have that much resolution. So how do you keep from just scanning noise.
Most inkjet printers for instance are 300 dpi, so for most prints, when you get into the 1600 dpi range, you are really just scanning all that noise and blowing up the file sizes.
Same thing can be set for color depth. If it is printed from a computer, then the chances are you are only going to need 8-bit of color, but with a real photographic process, you get way more dynamic range than this, so I like to scan at 16-bit grey or 48-bit color. Disks are so big, why not be archival.
And as another aside, you can also use your phone to scan photos as well since these are running at 12MP, but you will have parallax and other errors.