Preview is a deceptive piece of Apple software. It looks as though it’s just for reading PDF files, but it has some secret powers.
Did your cousin send you a dozen digital photos in that last email attachment? Of course you could load them all into iPhoto, but you could also view them with Preview.
Select all the photos in the Finder and choose File > Open With > Preview.app.
Preview opens and displays each photo on its own page within one document.
See a slideshow
Now in Preview choose View > Slideshow. Your screen goes black and after a moment the first photo is displayed. The next should appear after a few seconds, but you can also move forward and back with the right and left arrow keys.
The slideshow controller is also visible at the bottom of the screen. Controls include: Previous Page, Pause / Play, Next Page, Index Page (shows thumbnails of all photos), Fit to Page / Actual Size, Add to iPhoto, and Exit.
Screenshot 01: Preview is displaying half a dozen photos as one document. Screenshot 02: The slideshow controller is visible.
Try out the Add to iPhoto button purely for the extra cool animation that shows the photo being ‘sucked in’ to iPhoto.
Open an image, choose File > Save As… and then choose a new format from the Format pop-up. With some formats, such as PDF, further options may become available.
For example, you can make a PDF sepia toned, or reduce the filesize, or perhaps encrypt it. My 2.5Mb test photo turned into a 25Kb PDF, when I chose the Reduce File Size option, though the picture quality was also degraded.
Note: this article was written using Preview version 3.0.9 (409) on Mac OS X 10.4.9. Older versions of Preview may not include all these features.
Open a PDF and find a page you often need. Now choose Bookmarks > Add Bookmark. Edit the name of the Bookmark to make it more useful and click the Add button.
Screenshot 03: I encrypted this PDF; a password is required to open it. Screenshot 04: A bookmark allows you to open that page in that PDF even if the PDF isn’t open.
You might think a Bookmark allows you to find that page again easily, and it does, even if the PDF isn’t open. So long as Preview’s open, go to the Bookmarks menu and choose the bookmark. The PDF opens right at the relevant page.
Keywords and searches
Adding keywords to a PDF lets you use a Spotlight search to find the file.
I opened a photo of one of our new puppies in Preview and saved it as a PDF. Then I chose Tools > Get Info and clicked on the Keywords tab. After clicking the Add button I typed in a keyword.
I added ‘Oshi’, ‘puppy’ and ‘dog’ as keywords. Now the results of Spotlight searches on any of those keywords will include this PDF.
Screenshot 05: I’ve added two keywords and am about to add a third. Screenshot 06: My PDF shows up after a search because of the keywords I added, even though the filename is an unhelpful IMG_9364.pdf.
Remember to save your changed PDF if you add keywords.
Preview’s automator actions
Preview’s powers don’t stop there — make sure you have a good look through the menus and Preferences for further options for viewing PDFs and image correction — but extend to manipulating photos from within Automator.
Open Automator (in the Applications folder). Next select Preview in the Library column, and look at what’s available in the Actions column. You’ll see options for scaling and cropping images, as well as creating thumbnails and more.
Preview.app is much more than a PDF reader.
This article was first published in Macguide magazine Issue #33 May / June 2007 and has been modified from the original.