The libraries from Apples "Photos App" and from the old "Aperture App" are the reason why my phm crashed.
They are bigger than 10 GB and phm is trying to scan these libraries.
In the preferences of phm you can select which drive and folders phm should scan for pictures and movies.
My libraries (Photos App and Aperture App) are in my pictures folder in an own folder, and I deselect this folder in the preferences, so that phm not scan this folder for pictures. (Sorry, hope you understand what and how I try to explain. 
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PS: With aperture library I meant the library from the old App "Aperture" from Apple.