When you click the Edit button with an image selected in iPhoto, the internal editor opens. If you’d like to use a different image editor when clicking edit, follow the steps outlined below.

1. Open iPhoto and select iPhoto -> Preferences… from the main menu.



2. On the General tab, select drop-down menu next to Edit Photo:. Choose In Application… from that list.


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3. Navigate to the image editor you want to use to edit your iPhoto images. Select it and click Open.


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4. Exit out of the iPhoto Preferences.


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5. And now when you click the Edit button, your image editing application of choice will launch, and load the selected photo(s).