Top tips for Preview
Preview is probably one of the most used of the built in apps in OS X on the Mac. It can be used for viewing photos and other images, viewing and annotating PDFs and more. It has lots of useful features, but it is easy to miss some of them because they aren't obvious. If you have been using Preview for years, you might not have realised that new features have been added because you're using it exactly as you always have. Here is a collection of not-so-well-known features.
Open files and folders
To load a file into Preview, such as a .jpg photo, you can often click it in a Finder window or on the desktop. Some file types are associated with Preview and the app starts automatically and opens the file you clicked on. If another app has the association though, you can click and drag the file you want to the Dock and drop it on the Preview icon to open it.
What you may not have realised is that whole folders of files can be opened in the same way. Select several images or PDFs in a Finder window and then double click them. Preview will open them all. Thumbnails are displayed in the left panel and the first image is shown in the main window. An alternative to double clicking them is to drag them to the Preview icon in the Dock. It works just the same.
Another trick that Preview can perform is to open a whole folder of files. For example, if you have a folder containing lots of photos you can click and drag the folder to Preview in the Dock. Preview opens the folder and loads all of the files.
Browse the thumbnails
If you open several files in Preview, such as a group of .jpg images, the thumbnails are displayed in a panel on the left. The order of these thumbnails can be rearranged by clicking and dragging them. You'll see the other thumbnails scoot around as you drag a thumbnail.
Select a thumbnail and the image or PDF is shown in the main window. If you then press the up or down arrow keys you can view the other items. Press down arrow, for example, and the next item is displayed in the window. If the Shift key is held down as you press the up and down arrow keys you change the currently selected items, but not the current view in the main window. This is useful for selecting multiple thumbnails without losing your current view in the main window.
Apply actions to multiple files
With multiple thumbnails selected you can perform actions on all of the items. For example, File, Export Selected Images, or File, Mail Selected Images. You can also resize multiple images. Click and drag over the thumbnails to select them or Command+click the thumbnails you want and then select Tools, Adjust Size.
Click the View menu and then hold down the Option key. Several menu items change and you get Actual Size On All, Zoom All To Fit, Zoom All In, and Zoom All Out.
Select the first thumbnails and you can view a slide show. Press Shift+Command+F or select it in the View menu.
Sort the thumbnails
If you open several files at once, what order are the thumbnails in? Are they in the best order, the order you want to work on them? As pointed out earler, they can be manually rearanged, but this would be tedious if there were a lot of files. Fortunately, there are options to sort them by various criteria, although you won't find any options on the menus.
Right click in an empty part of the left thumbnail panel and a menu is displayed, Sort by. Follow the arrow and you have Name, Path, Date, Size, Kind and None. It is None that is selected by default and you can choose any of the others to sort the thumbnails.
Delete a file
If you want to delete a file just drag the Thumbnail to the Trash. It doesn't just close the file in Preview, it deletes it on disk too. You can also select one or more images and move them to the Trash on the Edit menu. You can also right click a thumbnail and select Move to Trash. The simplest method though, is to press Command+Backspace.
Show hidden toolbar buttons
The toolbar contains a small collection of buttons to access common functions. There are actually around 30 buttons available, but most of them are hidden. Right click the mouse in an empty part of the toolbar and select Customize from the menu. All the buttons are displayed in a palette and they can be clicked and dragged to the toolbar to add them. It's up to you which ones you have. For example, if you often print items then drag the Print button to the toolbar.
Go to the Tools menu and select the Move Tool. You can now click and drag a large image around in the window. To centre the image on any point, Command+click it. Open an image and select Tools, Adjust Color. A floating window appears with lots of controls for adjusting the image. It does a lot more than just change the colour and there is exposure, contrast, highlights, shadows, and sharpness sliders. It saves you having to open it in a photo editor or iPhoto.
* View multiple files in Preview
* Sort and resize Preview thumbnails
* Add your signature to PDFs