Printing Standard Prints with iPhoto

In traditional commercial printing and photography, a light table — a translucent piece of plastic or glass fitted on top of a box with internal light — is used for trimming photographic film negatives or positives and preparing them for printing in magazines, newspapers, books, and so on.

The professionals who know how to trim photos on a light table use words such as cropping to describe cutting away the outer edges of a photo, bringing the center of the photo to the forefront, and retouching to describe brushing away artifacts in the image.

Printing standard prints

Standard prints are what you get from a photo service. iPhoto makes conforming to standard print sizes with your color printer easy because it automatically resizes images to fit properly for the settings you choose. These settings are useful if you intend to use store-bought picture frames, which are measured for specific sizes such as 4 x 6 or 8 x 10.

To select a standard print size when printing to your desktop printer, choose these settings from the Print dialog box:

1. Choose the Standard Prints option from the Style pop-up menu.

2. Choose the appropriate size from the Size pop-up menu.

Don't choose a very large print size, such as 8 x 10, for a low-resolution image because the picture stretches over a large area and doesn't look as good as it does at smaller print sizes. You need a resolution of at least 1800 x 2200 pixels for a decent 8 x 10 print.

Although the Print dialog box offers many choices for printed photo sizes, you may need to adjust the proportions of your photo to fit certain sizes. Photos from most digital cameras are sized at proportions of 4 (width) x 3 (height), which is fine for computer displays, DVDs, and iPhoto book layouts, but isn't the right proportion for standard prints. iPhoto makes this adjustment easy with the Constrain feature for cropping.

Constraining cropping for print sizes

You can use the Constrain feature to crop a photo to a specific proportion. Constrain keeps the proportions accurate while you drag the cropping rectangle, so you don't need rulers, math expertise, or graphics skill to get it right for specific print dimensions. As you drag, the Constrain feature keeps the rectangle accurate.

The Constrain pop-up menu, to the left of the Crop button, offers a list of print sizes like 4 x 6 (Postcard), 4 x 6 (Portrait), standard 8 x 10, 8 x 10 (Portrait), and so on. You even find sizes such as 1024 x 768 pixels, for desktop pictures and screen effects.

iPhoto allows you to do precise cropping when you open your photo in a separate window. Open the photo in a separate window by holding down the Option key while double-clicking the photo. The Crop button and Constrain pop-up menu are available in the window's toolbar.

To crop a photo with the Constrain menu in a separate window, follow these steps:

1. Hold down the Option key while clicking the thumbnail image of the photo in the Viewer pane.

If you open the photo in a separate window, you can see the photo at different sizes.

2. Click the Constrain pop-up menu and choose a format.

3. Click in one corner of the area you want to crop and drag the mouse across the image to the far corner of the cropping area.

The mouse pointer turns into a crosshair. As you drag, the portion of the photo outside the area dims to show that it will be cut from the photo.

4. Adjust and resize the cropping rectangle.

If your cropping rectangle isn't perfect the first time, move your pointer anywhere inside the cropping rectangle until the cursor turns into a pointing finger and then drag to adjust the rectangle's position. You can also drag the edges of the cropping rectangle to make it larger or smaller, but still in the same proportion, because the Constrain feature is on: Move your pointer close to the edge or corner of the cropping rectangle and drag to make it larger or smaller.

5. Click the Crop button.

Be sure you want to crop the photo. Cropping changes the photo everywhere it appears.

The Crop button reduces the photo dimensions to the selected area, which, due to the Constrain feature, is in the correct proportion for your print or display choice. After clicking the Crop button, the photo consists of only the selected area; the rest of the photo is thrown away.