I have a 500GB spares bundle encrypted disk image that I store on a network drive, that contains around 200 video files (various formats: mov, mp4, mts) in its root level, plus a few subfolders.
Merely mounting the image takes only a couple of seconds. However, when I actually navigate the Finder to list its contents, it takes upwards of 2 minutes, with the Finder becoming unresponsive during that time.
The network connection is otherwise quite fast, with copy operations to/from folders inside the image being at the 1+ MB/sec range.
What can be causing this slowness and how can I work around it?