Ummm,,,,,, 2400 DPI is a
fantastically huge resolution.
A 1-inch square image @2400px and 24-bit color is around 6.35 megs. A letter-sized image would have to be at least 93.5 times that, or up near
600 megs for one image.
At that size, you could store--
--1 image on a CD,
--7 images on a regular DVD, or 14 images on a dual-layer DVD.
--a 200 gig hard-drive would only be able to store about 300 of these images.
Can you even work with a file this big?
I tried to resize a couple images as png's and jpeg's up to 26400 x 20400 pixels, using Photoshop 7--and it crashed every time (its
maximum limit is 30K x 30K pixels, and most image file formats don't even allow images that large anyway). Of course if some of these documents are B&W then scanning in greyscale saves a lot of filesize, but unless they intend to view these files greatly magnified, there's not much reason for the extreme detail.
They probably just looked at their scanner and saw that 2400 DPI was the maximum, and wanted it,,,, -but imaging at this resolution and size really approaches what is practical to store and retrieve on desktop hardware, using regular software--and there may be size limitations of PDF's anyway, I haven't even checked into that. A PDF
pre-loads all the images....... Assuming it allows that much image data, are they going to want a PDF that takes 5-10+ minutes to open on a typical PC? Probably not.
I would suggest that you ask that they consider a smaller scan resolution. Standard commercial printing is done at 300-DPI and 8-bit color; anything they submitted to a print shop that was higher-detail than that would probably just get downsampled anyway.
I would suggest you get a sample photo and scan it at 300, 600 and 800 DPI, and have these printed (by a commercial printer) and show what the difference is(n't). If the source document is color, leave one set of prints at 24-bit color and flatten a second to 8-bit color, and show them. (label these on the image before printing, you probably won't be able to tell the upper ones apart) My bet is that 8-bit color (or greyscale) @ 600 DPI is going to be sufficient.
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As far as scanning things without damaging them, there are archival scanners, also called book scanners. These typically cost up in the thousands of dollars.
www.imageware.de/en/ is one company that makes them.
A possibly-cheaper alternative is if you have a higher-megapixel GOOD camera (with macro focus), you may be able to use that with proper lighting. But even then--a good camera will run near $1000 itself.
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