Sort files in the Photo Browser

 Choose a sort option from the Photo Browser Arrangement menu to the upper right of the Photo Browser. You can choose from the following sort options:
Date (Newest First)
Shows the most recently taken or imported photos first. (Within a given day, the photos are shown in the order they were taken, oldest first, unless otherwise specified in the General Preferences dialog box.) Newest-first order is convenient when you need to attach tags to the photos you imported most recently.

Date (Oldest First)
Shows all the photos in chronological order.

Album Order
Shows photos in the order in which you placed them in an album (available only when an album is selected).

The Photo Browser Arrangement menu sorts the thumbnails in chronological, reverse-chronological, or album order.

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