I've used ArcGIS Collector to gather data, including images, which display nicely in the pop-ups on the map. However, the images are not visible in the attribute table and cannot be exported along with the rest of the data to an excel file (or any other data type). At least not in any way that I've found so far.
Has anyone come across a solution to this issue?
You might not have the attachments field showing in your table/data view. Just tick it on and you should see the attached files.
I think you will only be able to export the images by exporting as a file geodatabase. I use FME to grab attachments.