When a new version of an image is created in Aperture, a stack is automatically made and the original made the pick. This behavior is a problem when the user intends to adjust that new version, especially if hundreds of images need adjustment, because the adjusted image is not the stack pick, and so will never be used for exporting, printing, or anything else.
To access the new versions and apply adjustments, create an album that holds the original and new versions. By working with the album and making the new versions the album picks in the stacks, adjustments can be performed and exports made with no extra work. In detail:
Select all the images in a project you want to adjust, then create all the new versions at once with Option-V -- and do not deselect the new versions! Control-click on one new version and select New From Selection » Album, then rename the Untitiled album to something else. Close all the stacks in the new album with Option-semicolon. Notice that the stack picks have a check mark to show they are the album pick. Apply adjustments to the images in the album, either one at a time or all at once with lift and stamp.
If you look at the stacks in the project, you will see that the picks are not adusted. To export or use the adjusted images, use the album. To export or use the original images, use the project. This workflow can be used for any number of versions and any number of images. Just create a new album each time.
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