I’m not littlebird, but in many cases (and with the proper skills and training), photographing is a better option than scanning because you can get a higher quality, better-nuanced, more detailed, properly colored copy through photography than with a scanner. Particularly for items that are so large you’d otherwise have to scan in pieces and then meld together (only if the camera is high-enough resolution, though).
Scanners that are available to consumers are rarely of a quality that is good for archival purposes—they’re really calibrated more for scanning in financial documents and the like.