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Pro Tip: RAW vs. JPEG

(2007-09-05 08:12:25) 下一个


Filed under: Professional Photos — Penny Adams at 10:00 am on Tuesday, September 4, 2007

If you have a new higher-end camera, then you’ve probably wondered which image format is better to use: RAW or JPEG. There’s no easy answer as both have their pros and cons; it just depends on your work flow and how much you enjoy editing images.

First, a little background on the two formats: JPEG, an image file with a .jpg extension, is a common format used for storing and transmitting images via the web because the files are much smaller than those of other formats. It’s a lossy format, which means that more data is thrown away as the file is increasingly compressed. With low compression, it’s difficult to see a big difference between an uncompressed TIFF file and a high-resolution JPEG. To learn more about the technical side of how JPEGs work, check out this article.

RAW is an uncompressed, unprocessed raw data file that cannot be printed without first editing and converting it to another format. Think of this format as a film negative that still needs chemical development. When loaded in photo editing software, RAW files can be precisely edited without compromising the original file. Photographers can easily change the color and lighten, darken and adjust the overall contrast before converting the file to another image format that’s suitable for printing.

When you compare the two side by side, you’ll see which format is best for you. If you use JPEG, the camera will automatically processes the image information, such as color and contrast, for you. If the white balance has been set correctly and the image is exposed properly, then little or no processing is normally needed when working with a JPEG file. With RAW, you have the opportunity to make those choices manually with your computer. The RAW file contains twice as much data and information as the JPEG file (16-bit vs. 8-bit), which also means the overall file size is much larger, so less photos will fit on your memory card and more disk space will be needed to store the images.

Many photographers debate that when a photograph is taken at the highest quality, there is little visual difference between a processed RAW file and a JPEG file with minimal editing when viewing the finished prints side by side. Also, some cameras offer the option to shoot in both RAW and JPEG at the same time. This setting may be the best of both worlds for some. For more detailed information and to compare the two formats, visit this case study.

So, what’s your choice?

Shoot in RAW If…

    * Your primary concern is ultimate quality.
    * You aren’t concerned with storing large files on your memory card or computer.
    * You have a lot of time and editing experience to make changes to the images.
    * You generally take a few images at a time.


Shoot in JPEG If…

    * You want to use less memory-card and storage space.
    * You don’t want to spend a lot of time editing the images.
    * You often take hundreds of high-resolution images a day.

As I mentioned, there’s no right or wrong method; it just comes down to how you prefer to spend more of your time…behind the camera or behind the computer.

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