To convert negative to digital u need to have a good film scanner if u want to have a high res images or scan to tiff file. I used to scan my negative by using the Kodak Professional RFS 3570 Plus Film Scanner while I was working in the press, we start digitize our negative in 1992 and we use six Kodak scanners at a cost of RM35,000.00 each.

U can scan from the various sizes negative, 6x9, 6x7, 6x6,6x4.5 and 35mm, everytime u change the film size u have to calibrate the scanner. And resolution from 72 to 600 dpi.

A very good and fast scanner, to scan a image size of 6 mb and file size of 1.1mb with 300 dpi only take around 10 sec.

But now the scanner already discontinued but we still use it off and on. And I myself is using a Canon 9950 flatbed scanner which is good eough for my need. You don't have to go for really highress scanning unless u want to use it as poster size then u have no other choice but to get a good quality film scanner.