"more info" in Get Info showing "--" instead of actual infos for newer videos and images

I've just noticed that when I click on "Get Info" on my newer pictures and videos, the "more info" section is now showing "--" instead of the dimensions of the images and videos. However when I go to my older files, the info is showing. Also if I search any of the newer files (those with the missing info) in Spotlight, it doesn't show up. I've done some research and some people suggest reindexing Spotlight, but that never worked for me. In fact, even if I exclude a folder in my Privacy list, it's still showing as a result when I search them. I'm sure this is a problem with Spotlight as it stores the dimensions info, but since reindexing it is not a solution, can it be solved in some other way?