iPhone: Improve backup and restore times by reducing iPhone Camera Roll
Posted by Apple - Support - Most Recent - iPhone on Monday Mar 8, 2010 Under All, Support
Pictures and screenshots taken with the iPhone are stored on the Camera Roll. When you sync or perform a restore, iTunes creates a backup the contents of your iPhone, including the Camera Roll. The more pictures or other multimedia files that are on the Camera Roll, the longer a backup or restore will take.
Improve backup and restore times by regularly importing the contents of your Camera Roll, and then sync that content back to the iPhone.