It can be a better choice if you have a Photos library with tens of gigabytes of images or more paired with low-speed broadband (in the tens of megabits per second) or a monthly usage cap beyond which you pay overage fees or have your service throttled to a lower speed. That second option plus copying works because you have a full copy of all images present in your iCloud storage. But you can choose instead to copy your Photos library as if you weren’t using iCloud Photos at all. If you set Photos to keep full-resolution downloads of all images on your current Mac, you can also enable Photos for iCloud syncing as in the previous point.This can take a while and consume a lot of internet bandwidth. Photos automatically performs all the downloads necessary. If you have optimized media enabled on your current Mac, you can simply use the same iCloud account on your new Mac and set Photos up for either optimized or full-resolution mode.When you want to copy or move your Photos library from one Mac to another with iCloud Photos enabled, that presents you with two choices:

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