Why your Photos and iPhoto libraries take more space on a Mac’s external drive<article>
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<p>When you have an older iPhoto library and a newer Photos library on your Mac and you copy both libraries to an external drive, you might notice that they collectively occupy a lot more space than they do on an internal drive. Why is that? It comes down to hard links, a way of conserving storage.</p><p>When Apple released Photos for macOS in 2015, it had to have a transition plan for iPhoto libraries. iPhoto libraries could be imported and converted, but with a twist. Instead of copying all the source images, Apple used hard links, which allow a file to occupy a single place on a disk and be referenced in multiple folders as if it existed uniquely there. (You can read more about hard links in “
Upgraded to Photos? Here’s what you can do with that old iPhoto library.”)</p><p class="jumpTag"><a href="/article/3385121/why-your-photos-and-iphoto-libraries-may-occupy-more-space-on-a-macs-external-drive.html#jump">To read this article in full, please click here[/url]</p></section></article>
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Why your Photos and iPhoto libraries take more space on a Mac’s external drive