Apple Aperture Digital Photography Fundamentals - Manual (Page 22)

22 Chapter 1 How Digital Cameras Capture Images
JPEG
JPEG (Joint Photographic Experts Group) is a popular image file format that lets you
create highly compressed image files. The amount of compression used can be varied.
Less compression results in a higher-quality image. When you shoot JPEG images, your
camera converts the RAW image file into an 8-bit JPEG file (with 8 bits per color
channel) prior to saving it to the memory card. In order to accomplish this, the camera
has to compress the image, losing image data in the process. JPEG images are
commonly used for online viewing.
TIFF
TIFF (Tag Image File Format) is a widely used bitmapped graphics file format capable of
storing 8 or 16 bits per color channel. Like JPEG files, TIFF files are converted from RAW
files. If your camera does not have an option to shoot TIFF files, you can shoot RAW files
and then convert them to TIFF files using software. TIFF files can have greater bit
depths than JPEG files, allowing them to retain more color information. In addition, TIFF
files can use lossless compression, meaning that although the file gets a little smaller,
no information is lost. The end result is greater image quality. For these reasons,
printing is commonly done from TIFF files.
Shooting Tips
Here are some tips for dealing with common photography issues.
Reducing Camera Shake
Camera shake is caused by a combination of the photographer’s hand movements or
inability to keep the camera still, slow shutter speed, and long focal length. Camera
shake results in a blurred image. The focal length of the lens, combined with a slow
shutter speed, creates a situation in which the shutter speed is too slow to freeze the
image before the camera moves significantly.