Discover Preview’s hidden features for editing images and manipulating PDFs!
Take Control of Preview
Adam C. Engst
Apple’s Preview app is bundled with every Mac and yet many Mac users have only a shallow understanding of what it’s capable of. Mac experts Adam Engst and Josh Centers have plumbed Preview’s depths to create a cheerful, colorful book that explains dozens of techniques for importing, viewing, editing, and converting images in Preview. It also puts you in control of reading, annotating, manipulating, and encrypting PDFs.
All Take Control books are delivered in three ebook formats—PDF, EPUB, and Mobipocket (Kindle)—and can be read on nearly any device.
Apple bundles the Preview app with every Mac, but few people realize what it’s capable of. The Mac experts behind TidBITS, Adam Engst and Josh Centers, have plumbed Preview’s depths to create a cheerful, colorful book that explains dozens of techniques for importing, viewing, editing, and converting images in Preview. The book also puts you in control of reading, annotating, manipulating, and encrypting PDFs.
Packed with real-world examples and tips, the book teaches you how to bring files into Preview from a camera, iOS device, or scanner (or just from the Finder). Once you discover Preview’s surprisingly capable collection of image-editing tools, you’ll soon be editing imported photos by tweaking the exposure, color saturation, sharpness, and more. You can even mark up your images with circles, arrows, and text, plus numerous other shapes.
In the second part of the book, Adam and Josh focus on PDFs in Preview, describing how to configure Preview to make reading PDFs as fluid as possible. Since so many paper forms now come in PDF, the book shows you how to fill out PDF-based forms, complete with quick insertion of your digital signature. Those who read digital textbooks or who collaborate on documents will learn to annotate PDFs with highlights, notes, and bookmarks. You’ll even learn how to create PDFs from a scanner, the clipboard, and the Print dialog. Finally, Adam and Josh cover the two types of passwords you can use to protect your PDFs, explaining what each is good for.
Preview is a veritable Swiss Army Knife. Don’t miss out on the many ways it can make your life easier, including these capabilities:
Import photos from your iPhone or iPad.
Scan paper-based documents and images.
Add a scanned page to an existing PDF.
Take a screenshot that includes the pointer.
Open hundreds of images in a single window.
Trash unwanted images with a keystroke.
Duplicate, rename, and move images without leaving Preview.
Play a manually arranged slideshow of images or PDF pages.
Create a PDF-based image catalog.
Resize and change the resolution of images.
Crop out undesirable content.
Mark up screenshots with shapes and text labels.
Magnify a portion of an image with a loupe.
Add text captions and speech bubbles to photos.
Tweak the white point and black point in photos.
Make photos sepia or black-and-white.
Edit a photo while comparing it to its original version.
Export to any one of 20 formats, including HEIC (introduced in Mojave).
Put thumbnails, table of contents, notes, or bookmarks in your sidebar.
View search results by rank or page order.
Copy text and images from a PDF.
Highlight text just like you would in a college textbook.
Add notes to highlighted text and as freestanding objects.
Review notes in the sidebar or Annotations inspector.
Create bookmarks to pages you want to revisit quickly.
Annotate a PDF with customizable shapes and arrows.
Fill in PDF forms, whether or not they’re interactive.
Create and insert a digital version of your signature into PDF forms.
Add, remove, and rearrange pages in a PDF.
Rotate PDF pages that were scanned at the wrong orientation.
Encrypt PDFs so they can’t be opened, edited, printed, or copied from.
Josh Centers is the managing editor of TidBITS and a freelance writer who has written for Macworld, the Magazine, Boing Boing, and the Sweethome. He has been featured on Daring Fireball, the Loop, TUAW, and Scientific American, and is a frequent guest on MacVoices and the Tech Night Owl. He lives in Tennessee with his wife, Hannah, and their son, Harris.
Adam C. Engst is the publisher of TidBITS and the TidBITS Content Network. He has written numerous technical books, including Take Control of Preview and the best-selling Internet Starter Kit series, and many magazine articles—thanks to Contributing Editor positions at MacUser, MacWEEK, and Macworld. He has been turned into an action figure.
Although nearly three years have passed since the initial publication of this book, Preview itself hasn’t seen any major changes—it’s still the app you know and love. Most of what has changed came with the release of macOS 10.14 Mojave and is related Mojave’s new Continuity Camera and screenshot features.
Unfortunately, we’re sorry to report that, although Apple updated Preview to incorporate Mojave’s new capabilities, the company also introduced quite a few bugs and unwelcome changes, such as the Contact Sheet view displaying thumbnails as squares that squish the aspect ratio of the images or PDF pages they represent. We’ve called out such infelicities wherever possible so if you have trouble with Preview, you can verify that it’s Preview’s fault, not yours.
All that said, along with numerous small edits to bring terminology and versions up to date, this version of the book contains the following notable changes:
We rejiggered "Configure Preview Preferences" to match how Apple moved preferences around. The options aren’t particularly different, but they’re in new spots.
We added the topics "Importing from a Screenshot" and "Importing from an iPhone or iPad" to cover how you can bring content into Preview from Mojave’s new screenshot interface as well as directly from an iOS device. We removed mention of using iOS devices from "Importing from a Camera" now that Preview handles that through Mojave’s Continuity Camera feature.
We updated "Importing from a Scanner" significantly to match Mojave’s scanning interface, which has fewer options than in the past.
We added the sidebar "Preview’s Editing Tools Escape the App!" to note that Mojave’s new Markup tools work much as they do in Preview.
We added tips explaining the View > Show Image Background command and how you can resize multiple images at once.
We added some tricks in "Working with Shapes" for resizing, aligning, and layering shapes.
We added a sidebar about "Resizing the Image Canvas."
We added a discussion of the new HEIC image format in "Choosing a File Format" now that Preview can open and export .heic files.
We removed the section discussing how you can work with animated GIFs in Preview. As far as we can tell, that feature no longer works properly in Mojave’s version of Preview. It wasn’t particularly useful before, so it’s no great loss.
We added some notes and warnings in "Annotate PDFs" to warn users about new annotation-related bugs in Mojave’s Preview.
We edited a lot of screenshots so they show the new Markup button instead of the old one. Thanks, Apple!
macOS 10.12 Sierra has been plagued with PDF problems. First, there were problems with PDFs created using ScanSnap scanners, but those issues turned out to be relatively mild and Apple addressed them in the 10.12.1 update.
Unfortunately, 10.12.2 Sierra ushered in even more troubling issues with PDFs. Developers have reported a number of PDFKit problems, most notably the OCR text layer being deleted when manipulated by apps using PDFKit, including Preview. The main takeaway is that you shouldn’t use Preview to edit PDFs until these issues are resolved, hopefully in 10.12.3. In the meantime, if you have to edit a PDF, either work only on a copy, just in case, or consider investing in Smile’s PDFpen, which annotates and edits PDFs independent of Apple’s PDFKit.
[Fixed? In the release notes for the 10.12.3 Sierra update, which were made available on January 23rd, Apple says that the update “fixes an issue that prevented the searching of scanned PDF documents in Preview.” Other PDF-related problems appear to remain in Preview, so continue to work with caution even after you install this update. See Apple Releases macOS Sierra 10.12.3, iOS 10.2.1, tvOS 10.1.1, and watchOS 3.1.1, in TidBITS, for more information. —Tonya, 1/24/2017]
Elisa Pacelli of MyMac.com reviewedTake Control of Preview, saying “Once again, TidBITS hits it out of the park with their latest book.” Pacelli offers a summary of Take Control of Preview and shares a few of her favorite parts. “Some tips can literally be life changing,” she said.
When you add text boxes and shapes to an image, they’re added in layers corresponding to the order in which you created them. For example, a rectangle created after a text box will obscure the text if you position it over the text, which may not be desirable. Other graphics apps tend to have Bring Forward and Send Backward commands to rearrange objects, but Preview lacks any such controls. Here’s the workaround: Option-drag the bottom shape to create a duplicate, which is newer and thus will appear on top of any other object. After making and positioning the duplicate, you can delete the original object.
July 14, 2019—We hope to release an update to this book to cover changes in Catalina and iOS 13/iPadOS 13 later in 2019.