In QGIS 3.14 / QfieldSync there is now the functionality to configure photo naming. Yay!
I use a 1:n set-up for photos, i.e. I capture photos in the child table ('photo') of a one-to-many relationship. I would like to name my photos based on attributes ('type' and 'num') in the parent layer ('tree').
So far, my attempt at the expression is as follows:
This isn't working.