The other day I had a photo to scan which was too big for my flatbed scanner. That's no problem--you just scan the image in multiple parts and then join the parts together in your photo editing software. I've written about this in the past when it was a manual process, but with the PhotoMerge feature in newer versions of Photoshop and Photoshop Elements, it was done in a about 10 seconds. So the next time you need to combine a multi-part scan together, don't forget the PhotoMerge feature. And if you don't have Photoshop or Elements, there is panorama software which works in the same way. Your software might even have a panorama stitching tool built in to it already.
• Photoshop's PhotoMerge Feature
• PhotoMerge in Photoshop Elements
• Stitching a Two-Part Scan Manually
• Panorama Stitching Tools