Requirements
The Sophora server (at least version 4.13.0) creates the required node type, mixins, properties, childnodes, select values, form field group and document changing script automatically on restart, so that nothing has to be imported manually.
Setup
In order to use the Sophora IPTC Add-on, the administrator needs to add the mixin sophora-extension-mix:imageMetadata
as well as the form field group "IPTC/EXIF" to the image document type on which the add-on should be used. Now the image document type has a new table field for the image metadata. Finally the document changing script "Copy image metadata to document" needs to be published before one can use the add-on.