Comparing Images in the Viewer

Now that our workspace is set, let's take a look at your options for comparing images. Aperture offers several Viewer modes that let you designate how the Viewer displays your images. If your system has multiple displays, you can even configure your primary and secondary displays to show single or multiple images simultaneously.

1.	On the control bar below the Browser, click the Viewer Mode button and choose Multi from the pop-up menu. By choosing Multi you can alternate between viewing a single image or Shift-click to view multiple images in the Viewer. Select up to ten images from your Browser to be displayed in the Viewer for comparison.
2.	Click the Viewer Mode button and choose Primary. Choosing Primary allows you to see in the Viewer the single image that you select in the Browser.
3.	Click the Viewer Mode button and choose Three Up. If you select one image, your Viewer will display three images: your selected primary image and the two images on either side for comparison.
4.	Click the Viewer Mode button again and choose Compare.
5.	Click any image in the Browser and press Return. This sets the image you selected as the compare item.
6.	Click another image in the Browser. The Compare mode provides an advanced method of evaluating one image against other images. Notice the yellow border around the compare item. Let's use the Loupe tool here to compare the image focus. To activate the Loupe, click the Loupe icon from the toolbar, or press the tilde key located above the tab key on your keyboard. Once you're finished, press the tilde key again to return to the Selection tool.
7.	Press the Left or Right Arrow keys to navigate to another compare image, to see how the feature works.
8.	Click the Viewer Mode button and choose Stack. Then select the first image from your Browser. Stack is the final Viewer mode. In Stack mode, the current pick is the primary image. Although this mode is similar to Compare, it works specifically within stacks of images.
9.	Press the Left or Right Arrow keys to navigate, and compare the primary pick to others in the stack.
10.	Press Command-\ (backslash) to set another image as the primary pick. Note Clicking an image that is not part of a stack will cause the Viewer to revert to Multi mode.