It may help to know I'm using the ArcSoft photo studio to scan and import, not the MP Navigator package it came with (that seemed oriented towards novices). I don't care what the output size of the file is. I am scanning only line-art transparencies and want at least 2400 dpi scans.
I just bought a Canon CanoScan 5600F scanner. It claims (on the box and elsewhere) 4600dpi is possible. "...at up to 4,800 x 9,600 optical and 19,200 x 19,200 interpolated dpi"
I had a previous scanner that could do 1200, but this is not enough resolution for the project I'm on. However, the new scanner does not seem to allow any setting above 1200dpi in any mode (Advanced, etc).
I cannot find and answers in the manual or online. Thanks for any help you can offer...