As well as a powerful editor, Aperture is a great organisation tool for all of your photos. With so many ways to organise your shots, from keywords to places, it’s easy to see why all kinds of photographers use it for their photos. But when it comes to adding your images to your Aperture library, the whole file can quickly become bloated and take up tens, if not hundreds, of gigabytes of space on your hard drive.
One of the reasons for this is the way that Aperture creates previews of your images. By default, it will create a preview for every image in your library in JPEG form. These make it simple to drag-and-drop images from Aperture, or add them to other apps via the Media Browser. But you can control their size to save gigabytes of space – here’s how.
1 Back it up
Before you do anything, make a backup of your Aperture library. In Finder, open the Pictures folder and drag the library onto an external drive to ensure it’s saved properly.
2 Check the backup
To check the backup is working properly, double-click the library on the external drive. Check the Get Info panel and make note of the library size, then re-open your Mac library.
Aperture saves Previews that can be dragged and dropped out of Aperture, but they take up a lot of space, so let’s reduce their size to save some disk space on your Mac.
4 Previews settings
Open Aperture’s Preferences from the Aperture menu, then choose the Previews tab from the menu. You’ll see the options available to you for reducing the size here.
Aperture will have set your Photo Preview setting automatically, but you can change it from the drop-down menu. Our default was Don’t Limit, which takes up the most space.
6 Size options
You can reduce the size from the preset options. You can make them very small but this will reduce the maximum size of images when you use them outside of Aperture.
7 Preview quality
You can also reduce the Photo Preview quality. You won’t notice any difference above ten, but go below six and you’ll get some artefacts in your images. Eight is a good compromise.
8 Apply to all
Changing this setting won’t adjust your current Previews. To do that, choose the Photos view, hit Cmd+A to select all, then right-click and choose Update Previews.
9 Check the difference
After the changes have applied, close your library and open its Get Info panel once again. If it’s worked properly, this should have shaved off a chunk of the file size.
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