I have More than 300 GB of photos and movies ( perhaps many duplicated)scattered on two MacBooks, one PC and one iPhone. I needed to tidy up the photos. Also I realised that I have no space on MacBook anymore and I am forced to use iCloud, to pay £7 pounds a month.
So I decided to take the ownership of my photos. I have two 1TB external disks.
1- copying from Windows was the easiest. Just copy the photos to External disks.
2-from Mac books; I simply, but gradually, not in one go, copied photos from Photo app onto USB disk( .mov, .jpg and HEIC files,..)
3-for iPhone, I used Airdrop to copy group of under 30 files at the time from iPhone onto a folder in Mac( I could directly copy to USB external attached to Mac). I tried to attach USB disk to Mac only when I have to. I was concern about Mac crash and corrupting USB.
It took a long time. But now I have the ownership of my photos and are mirrored onto two external disks. I deleted all the photos from Photo app. And now I have more than enough space on the Mac and have organised my photos on USB disks and not tied to any specific App.
Or cloud( Windows, icloud or google)
Some note.
-I am using dual boot and found Windows much easier to work with files e.g. repair USB and also mirroring folders( using robocopy)
-Photo App as many mentioned was not able to import from iPhone properly and in my case it crashed itself or the whole MacOS and consequently corrupting USB disk, where MacOS could not recognise let alone repair. Windows is much user friendly when you need help. It recognised the corrupted USB automatically and repaired it in less than a minute. Mac OS did not even recognised it.
3-Microsoft has kindly provided drivers for HEIC format where now I can view them in Windows OS.
Somehow this experience has shown me that I have started to use Windows more and more and found it more user friendly and less restricted that MacOS,