For several days now I've been trying to free up space on my MacBook by backing up and removing a large number of photos and video clips.
I removed most of them from Photos but couldn't understand why my hard drive was still pretty full?
Running a Disk Doctor scan, I found that 5000 items were residing in the old iPhoto Library - it seems when iPhoto "upgraded" to Photo it left the original Library intact and mirrored them in the new Photo Library taking up twice the space!!
Now going to look into ways of storing the photos etc externally and only bringing them into iMovie/Final Cut as required?