Scanning: Glass Negative Scans

[BAWilliamson]

(I mistakenly first posted this under Events. Sorry!)

This is my first post to RetouchPRO. I am using an Epson Perfection V700 PHOTO scanner to scan about 500 original B & W glass negatives from the 1915 San Francisco World's Fair. I have about 175 each of 8 x 10, 5 x 7 & 4 x 6 size glass negatives.

For all of the scans I want to be able at a later date to take a scan and enlarge it to perhaps a good quality 2' x 3' poster, as well as make other original prints or use in a high-quality book of photos that would be offset printed.

Right now I am planning to scan at 600 dpi for the 8 x 10 size and save the scans as a TIFF file. This creates about a 50 MB file. Is this large enough? I am looking for advice as to what specific dpi I should set for the two smaller sizes in order to have a similar file size and make the same kinds of enlargements.

The negatives are in varying conditions, ranging from excellent to fair. Am I correct that I should NOT make ANY adjustments with the scanner, but just use an absolutely raw TIFF scan and wait until such time as I am going to print and then make a copy and retouch in Photoshop? What about saving printer/scanner profiles? Should I ignore them as well?

Thanks for your help! I am looking forward to learning a lot here!