The Bulk Photo Uploader needs the photographs to be labelled with the UPN's or Student ID's.
Need a list of students and student ID's? Not a problem!
Pop into Reporting > Reports > Custom Report
Tick to include UPN, Student ID, Year and Form groups and click 'Choose'
Run this report and use the top right hand side Export icon to export this to Excel.
Once this is done you can send this file to the photography company and they can match up the students for you.