It’s tip time!
Sync your iPhone a few times incorrectly and you may end up with a mass of stubborn photos that just won’t ‘delete after syncing’ to iPhoto.
Over time this could become a huge collection of photos gobbling up precious storage space on your device, and this juggernaut of photos becomes far too many to erase by hand. You would already have these photos in iTunes and when it asks if you want to delete after import it will never select these because they have already been imported. You’ll have identical photos in iPhoto and your phone, but you can’t get the pics off your phone.
Fix this with these steps:
- Open Image Capture
- Check “delete after import”
- Drag and drop all items to a folder
- Import into iPhoto, telling it to ignore duplicates
- Clean-up the now unneeded items
Source: wirededucator.com