5x7 @ 300dpi would constitute 1500x2100 pixels

so 1500/4=375
2100/6=350

So, to be on the safe side scan at 400DPI. That should be enough to print your pictures at a nice resolution. If you want to print go higher like 600DPI. You should be able to calculate the required res :) 400DPI would give you a file of 1600x2400. This gives a TIFF file of around 11MB

Message edited on: 08/13/2005 16:16

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