Inside Photoshop® CS

Choosing Image Compression and Quality Settings

The number of photos a film camera can take is dictated by the number of exposures on the roll of film you use. With digital cameras, the number of exposures that will fit on a memory card is controlled by the following factors:

• Sensor size of the camera. Larger sensors produce bigger images and fewer photos per memory card.

• Resolution. Some digital cameras allow you to change the physical dimensions of the images created by the sensor.

• Type of image. In addition to JPEG, some cameras can save images as TIFF and RAW images; some of these formats save files in larger sizes than do others, so the format you choose determines how many images you can save to a single card.

• Quality levels. On most consumer ...