When you digitize slides, it's essential to get good starting points. Choosing the scanner and organizing the scanning process can make a huge difference in the results. Don't forget to learn how to set up the scanner and the scanning software properly. You might want to modify the default settings to enable extra features. Most scanners will require the emulsion side to be placed in a certain way. Sometimes it might be worthwhile to remount slides. The whole process might be long and arduous, especially if you want the photos to be neatly organized.
Digitize Slides Fast and Efficiently: Glass Slide Scanning
Digitize Slides Fast and Efficiently: Glass Slide Scanning
Source: http://conorcahill.blogspot.com/2009/02/digitizing-slides.html