When you email, print, publish, or export a photo from your iPhoto library, iPhoto asks you to choose the size, also known as resolution. The settings you choose depend on what you want to do with the photo.
To change a photo’s size or file format, you export the photo. You might want to export photos so that you can import them into another application.
To export photos:
Select the photo or photos you want to export.
Choose File > Export.
At the top of the Export Photos window, click the File Export button.
To specify the file type for the exported photo, choose an option from the Kind pop-up menu:
Original: Exports the photo as it was originally imported into iPhoto, before editing.
Current: Exports the photo in its current format. If you imported a RAW-format photo and then edited it in iPhoto, the photo is exported as a JPEG file.
JPEG: If you choose this format, choose an option from the JPEG Quality pop-up menu. The higher the quality, the bigger the photo. For example, if the photo will be used on a website where optimal quality for printing isn’t required, you could choose Low to save storage space on the website.
TIFF: A lossless file format that works well for transferring photos between computers and applications.
PNG: Another lossless file format popular for web images.
To change the size (resolution), choose an option from the Size pop-up menu:
For photos to be emailed or mainly viewed onscreen, these settings compress the photos (making them smaller):
Small: Use for photos you email or publish to websites where you don’t expect anyone to download and print your photos.
Medium: Use when you or your recipients have a reasonably fast Internet connection, such as DSL. This setting is not suitable for making prints.
Large: Use this setting when you and your recipients have a very fast connection. This size can be used to print small to standard-size photos (2 by 3, 3 by 5, and 4 by 6 inches).
For photos to be printed or published for download, these settings provide maximum detail for final prints:
Optimized: Use for larger prints and for publishing photos to your MobileMe Gallery for others to download and print. With this setting, photos are slightly compressed to a smaller file size so that they download faster without compromising quality.
Actual Size/Full Size: Use to make high-quality prints in small to large sizes, or to upload photos to your Gallery so that others can download and print them. This setting matches the actual size of your photo, so it may take longer to upload or download.
WARNING: MobileMe will be discontinued on June 30, 2012. You will no longer have access to your MobileMe Gallery after that date.
Specify your other options:
Include checkboxes: If you choose JPEG or TIFF from the Kind pop-up menu, you can include titles, keywords, and location information with the exported photos by selecting the checkboxes.
File Name: Choose whether to export photos in sequence, or by their filenames, iPhoto titles, or album name.
Prefix for sequential: If you choose Sequential from the File Name pop-up menu, you can specify text to appear before each number (for example, Birthday01, Birthday02, and so on). This step is optional.
Choose where to save the exported photo files, and then click OK.
iPhoto works best with JPEG files, the standard format for data compression of still pictures. If you experience problems working with a non-JPEG file in iPhoto, use a different image-editing application to convert the image to JPEG.