The best photo scanners provide reliable results for the desired purpose, whether that’s quickly digitizing boxes of 4-by-6 inch prints, scanning old film or negatives or scanning snapshots to share ...
If you're like most people, you have a multi-function fax/print/scan device that you use for scanning, or you just use your smartphone. If you're a little more serious, maybe you also have a flatbed.
I have about 7,000 35mm slides (mostly in Kodak carousels) that I would like to convert to digital images. I figure that employing a commercial service would be hideously expensive for that quantity ...