3.3

Chapter 5 Displaying Photos in the Viewer 117
To delete JPEG previews for a photo selection
In the Browser, you can select one or more photos and either delete or update the
JPEG previews.
1 In the Browser, select a photo or group of photos whose JPEG previews you want to delete.
2 Choose Photos > Delete Previews.
To update JPEG previews for a photo selection
1 In the Browser, select a photo or group of photos whose JPEG previews you want to update.
2 Choose Photos > Update Previews from the shortcut menu.
To force the rebuilding of JPEG previews for a photo selection
1 In the Browser, select a photo or group of photos whose JPEG previews you want to force
Aperture to update.
2 Hold down the Option key, then choose Photos > Generate Previews from the shortcut menu.
Rescheduling JPEG Preview Maintenance
Preview maintenance can be rescheduled for projects in which automatic preview maintenance
is turned o.
To reschedule JPEG preview maintenance
m In the Library inspector, select the project whose JPEG previews you want to start updating
again, then choose Photos > Update Previews.
Note: Each time you open Aperture, it checks for out-of-date previews in those projects whose
automatic preview maintenance option is turned on and then schedules the previews for
regeneration. If you don’t want previews updated automatically, turn o automatic preview
maintenance for your projects. For more information, see Controlling Previews with the Library
Action Pop-Up Menu on page 116 .
Rendering Preview Images
Aperture renders preview images in four situations:
•
When a library is upgraded—provided that the “Create previews for existing images” checkbox
is selected in the Welcome to Aperture dialog
•
When a photo is imported, or a version is created, rotated, or adjusted—provided that the
Maintain Previews item is selected in the Library Action pop-up menu (with a gear icon)
•
When you select the library, a project, or a photo selection and choose Photos > Update
Previews
•
Immediately before a slideshow, if the previews are not up to date, and the slideshow preset
uses the Best quality setting
When rendering a group of preview images, Aperture uses the current application preference
settings for compression quality and picture size, not the settings that were specied when
preview rendering began. For example, if you have the quality set to 6, and then halfway through
rendering you change the setting to 8, the previews that have not yet been rendered will be
compressed at setting 8. Previously rendered previews are unaected.
To update previews to use new size and compression settings
1 In the Browser, select the photos you want to update.
2 Hold down the Option key, then choose Photos > Generate Previews from the shortcut menu.