Nature Photography Photo Workshop

5.4. DIGITAL PHOTO STORAGE

Ones and zeros, bits and bytes are the new "film." Electronic storage is fundamental to digital photography; the systems and devices you use to record the original capture and work with the pictures in the computer make a big difference in your workflow and the protection of your photographs.

5.4.1. CAPTURE FILE FORMATS

The way your camera saves files onto the memory card makes a difference both in image quality and the number of images you can fit on a card. Most cameras offer two basic choices: JPEG and RAW. (Some cameras also offer TIFF format.)

Your camera saves a JPEG file by rendering the captured data, applying any active style settings, and compressing the file to reduce the size. Your camera offers several levels of quality for saving JPEGs. These quality levels are based on the amount of compression: higher quality preserves more data and results in larger files, and lower quality discards more data and yields smaller files. When the camera is compressing data to save a JPEG, a lot of the original capture data is discarded; this data can never be restored. See 5-25 for an example of destructive JPEG compression.

The main advantage of JPEG is that you can fit more photos on a memory card; another advantage is that you can immediately view the files without additional processing and share them with other people by e-mail and on the Web.

A typical RAW capture is not compressed. The data from the sensor is encoded in a specific way based on the ...