During registration, attendees can upload images or documents. Event admins can easily access these and download them through the Attendee Analytics.
Download the Files Uploaded During Registration
Go to Attendees > Attendee Management
Find the registrant and click on their name
Under their Profile, go to the Custom Fields section
Look for the question that asked the attendees to upload the file
Click Download
Note: The fields that would show up in this menu are attendee fields, not ticket buyer fields. If you're collecting only buyer information, make sure that the attendee fields are active, before you change the setting to collect buyer information only.