Backup file too large

Hi All

I updated to IOS10 and it crashed, leaving the 'plug into itunes' symbol

I've recovered the phone (6S) and all works fine, but when I try to restore from the backup (via iTunes) it says there's not enough space on my device (probably due to the extra space used by IOS10)

I know that most of the backup data is taken up by photos that can be deleted - is there any way to edit the backup file so I can recover my other files?

Thanks!