There is a huge amount of blank space around the thumbnails in order to hold information about them. However, regardless of how much info is displayed, it will always appear the same size. There seems to be no way to remove the extra margins around the thumbnails. If there is no text displayed under the thumbnails, it would greatly increase visibility to have the margins shrink accordingly. Maybe a view where only the thumbnails are visible? Or maybe some dynamic system that grows and shrinks the thumbnails based on how much info is under each.
Dynamic would not work, depending on the metadata we would have possible different heights of the thumbnails within a row. Go to the digiKam settings under View and enable only the information you need. By the way, if the smallest thumbnail size is set, almost all information in the thumbnail is automatically deactivated in order to be able to display a large number of thumbnails in the window. In digiKam-8.1.0 we added a lot of new metadata information in the right sidebar in the Properties tab. Maik
Icon view Settings: https://docs.digikam.org/en/setup_application/views_settings.html#icon-settings Maik