How do I use RAW images?

    13-Apr-2009
    8200494800

    Solution

    What are RAW images?
    RAW is the name given to an image file type that records image data captured by the camera's image sensor without any processing; it takes the name "RAW" because the data is raw. RAW images have the characteristic that the file sizes are larger than those of JPEG files. When handling the RAW images on a computer, use special applications for RAW images.

    When recording JPEG images used with most digital cameras, the image data is processed in the camera to adjust image quality to a suitable level so that it can be used right after being imported to the computer. However, because JPEG data deteriorates whenever it is edited and saved, repeating those functions will cause a loss of image quality.

    In contrast, RAW images need to be processed by special software before they can be manipulated with image-editing software. In this case, there is no deterioration of image quality when images are saved, so you can edit and save the images multiple times until you are satisfied with them. RAW images taken with your camera appear on the computer as files with a [.CR2] extension.
    CAUTION
    Settings cannot be made for DPOF prints when using RAW images. However, DPOF print settings can be made for JPEG images if the camera is set to record in both RAW and JPEG images simultaneously.

    Types of RAW Images that Can Be Recorded with EOS REBEL T1i / EOS 500D
    This camera's Image-recording Quality Settings for RAW images are as follows:
    QualityPixelsPrint SizeFile Size
    (MB)
    Possible shotsMaximum Burst
    RAW
    (RAW)
    Approx. 15.1 megapixels (15M)A3 or larger 20.2909
    RAW+JPEG +
    (RAW + Large/Fine)
    20.2+5.0724

    Using RAW images on the computer
    Most image-editing software cannot display RAW images, so some processing is required to open them. "Processing" means converting the RAW images to an appropriate file type such as JPEG so that the file can be manipulated on the computer.
    When processing RAW images on a computer, the images will be converted in accordance with the settings (such as Picture Styles) specified in the camera at the time of shooting. Also, the images can be edited using image-editing software in addition to the parameter settings described above.
    Once a RAW image has been processed, a new file will be created in addition to the original RAW image. The modification only affects the newly created image so that you can keep the original RAW image. This enables you to repeat the processing until you are satisfied with the image.

    To process RAW images, you need to use Digital Photo Professional, ZoomBrowser EX (for Windows), or ImageBrowser (for Macintosh).
    The software to be used depends on the computers you are using and your intended use.
    For more information on each application, please refer to the supplied documentation.