The instant alpha tool can be found in the Markup toolbar. (Using Instant Alpha, you can remove the background from around an object, such as these glasses, making it easier to copy them for later use.) Instant Alpha works by making selections based on color matching, making it an ideal tool when there’s distinct difference between the object and the background. It allows you to remove an object from an image, or remove the background from around an object. Instant Alpha: This tool has been included with the Preview app for some time. Preview offers two tools to perform this task: the Selection tool, which allows you to draw a rectangle, an elliptical, a free-form lasso, or a smart lasso around the desired object, and the Instant Alpha tool, which can perform a selection based on colors of objects. One of the problems with selecting an object is the difficulty in performing a precise selection to isolate the object from the background. Preview has a number of tools that allow you to select an object and copy or remove the selected object from the image. This means you will lose all of the edits you made, even the ones you might want to keep. Optionally, you can make use of the Revert to command in the File menu to return to a previous version of the file that existed before you made any edits. This will ensure any changes won’t affect the original file. Give the file a new name, then use Save from the File menu. This can be done by after opening an image in Preview by selecting Duplicate from the File menu. Earlier versions of the image are history.įor this reason, I highly recommend that you work on a duplicate of the image file. In other words, if you want to change an image back to the way it looked earlier, chances are it’s too late.

The practical aspect to this is that Preview will use destructive editing by automatically periodically saving the changes you make to the file you’re working on. This means that Preview will automatically save a document as you work on it. Preview is one of the apps that work with the Mac’s auto-save system. While it’s not a full-featured image-editing app, Preview does have some remarkable capabilities that make it a good choice for working with images, especially when you consider it’s supplied free as part of the macOS.ĭestructive Editing, Auto-Save, and Versions You can use the instructions from the Mark it Up with Preview guide, linked above, to access the Markup toolbar. We’ll be using Preview’s Markup toolbar, which is usually hidden. In Part Two of the guide, we’ll look at how Preview can be used for viewing and editing images. The Preview app is a handy tool for viewing and working with PDF (Portable Document Format) files, as outlined in the Rocket Yard guide: macOS 101: Mark It Up with Preview.

Edit photos in preview