Specific Aspect Ratios

If you want to order prints of a photo, you first should crop it to the appropriate aspect ratio (Figure 4.19). See the opposite page to learn about cropping photos and see "Understanding Aspect Ratios" in Appendix A, "Deep Background," for more details about aspect ratios.

Figure 4.19. Before cropping, choose the aspect ratio that matches your intended use.

Uses for specific aspect ratios:

• Use 1280 x 1024 (Display) before you crop the image for use as a Desktop picture. These numbers are specific to your monitor's resolution.

• Use 4 x 3 (DVD) and 16 x 9 (HD) for a landscape image for a DVD slideshow created with iDVD.

• Use Square when you want a square selection; I've found it helpful for making images for use on the Web.

• Use a custom ratio if some external use, such as a Web page, calls for a specific aspect ratio (Figure 4.20).

Figure 4.20. For an unusual custom aspect ratio, choose Custom and enter the desired aspect ratio in the Custom Constrain fields in the dialog that appears.

Tips

• iPhoto assumes you want to crop in the same orientation as the photo, but you can change that. See the sidebar to the right for details.

• iPhoto has some duplicate aspect ratios, presumably for people who don't realize that aspect ratios are ratios between numbers and multiplying those numbers by some value doesn't change the ratio.

• Don't bother cropping for books, cards, and calendars; it's better to use the zoom and pan feature instead because the zoom and pan feature doesn't modify the original image the way cropping does.

Switching between Portrait and Landscape Orientation

You may often find yourself wanting to switch between the constrained portrait (vertical) and landscape (horizontal) aspect ratios as you crop different photos, and you may also find yourself cursing a specific aspect ratio as you try to select a person's eyes to reduce red-eye. iPhoto has two hidden features to assuage your annoyance.

• Press while dragging to switch between portrait and landscape. This trick has the same effect as toggling the Constrain As menu item.

• Press while dragging to switch temporarily to None so you can more easily select eyes for red-eye reduction.