I used an older Epson scanner with a transmissive cover to scan 4x5 transparencies. The resolution was fine for creating an index, or perhaps printing as large as 8x10. If you care about your images, and want to extract every detail that is in the negative, use a medium or large format scanner (Nikon 9000, Imacon). But expect to shell out many thousands for these, and you often have to deal with connectivity and driver issues.