When the “generate Previews” option on the Catalog Administration Previews tab is enabled, Portfolio will create full-sized 72-dpi JPEG preview images when items are cataloged.
Previews are stored in a folder you designate, which can be on a local device, or on a file server. This means you can have the item source files anywhere—even offline (such as on a CD)—and users will still be able to preview the items. Additionally, having larger Preview files available on disk can make opening image Preview dialogs much faster.
Note: The Preview directory must be accessible to all users.
Note: Selecting a higher quality preview JPEG will result in larger files being created.
Multimedia files (movies, sounds, etc.) and files that cannot have thumbnails generated will not have Previews generated. If Generate Preview is enabled, Portfolio will always attempt to generate a Thumbnail and Preview (thumbnails will not be extracted). The Preview for multi-page items will be generated from the first page. You can also designate the quality of the JPEG Preview, either High, Medium, or Low.
To prevent excessively large disk files from previews, the maximum size of the long side of a preview image is 1000 pixels. You can set the Maximum Size to any value between 100 and 1000.
Tip: Do not select the same folder for both Disk Previews and Background Cataloging. Doing so will cause Background Cataloging to fail.