Hi @darrenbachan
ACF saves the image ID instead of the image URL in the database. Please use the get_field() or the_field() function to get the processed value. This page should give you more idea about it: https://www.advancedcustomfields.com/resources/image/.
Also, please take a look at this page to learn how to get the value from a user: https://www.advancedcustomfields.com/resources/how-to-get-values-from-a-user/.
I hope this helps 🙂