FYI, I've made a digikam-5.x copr,
https://copr.fedoraproject.org/coprs/rdieter/digikam/
for testing/feedback, and to help with dependency reviews tracked via bug,
https://bugzilla.redhat.com/show_bug.cgi?id=digikam-5.0
The current optimistic plan is to remove support for kde4-based kipi-plugins
from f24 (since they currently do not easily install in parallel with
digikam5's kf5-based versions).
kde4-based applications that currently use libkipi, but not yet ported to
kf5 include:
kphotoalbum
ksnapshot
The latter (ksnapshot) is deprecated by
kde.org upstream in favor of
spectacle (not packaged and reviewed yet, as far as I'm aware).
-- Rex