Scanned documents can require a large amount of disk space, and you should plan for this before embarking on a major project.

Just as the amount of time taken to fax a document varies, depending on how much text it has and the resolution you are using (coarse, fine, super-fine), so
does disk storage space. If a document has a lot of small print, it will take more disk space; if a lot of it is blank (like most invoices and business letters), it will take much less space on the disk.

200dpi is the resolution of most faxes. At this resolution, a full A4 page took 125kb, or 8 pages per megabyte of disk space.

A 150dpi image makes the text look fuzzier but saves some space. A full A4 page took 80kb, or 12 pages per megabyte.

At 150dpi, the text looks fuzzier than a 200dpi image, but it was still quite readable, both on the screen and when printed out. And at 44kb per page (23 pages per megabyte), it is the champion in disk storage efficiency.

If you want, you can use 300dpi (the resolution of most laser printers) or even 600dpi. Disk storage will go up rapidly (with our sample, about 250kb at 300dpi),
but of course the image will be sharper. There is nothing to stop you using higher resolutions selectively for the documents that need them.

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