Understanding File Formats
One of the many menus on a digital camera will offer you a choice of how you save the images that you take. The choice is between jpegs, Tiffs, and RAW files, and the type you choose will depend on the way in which you want to use your photos.
Jpegs are the smallest of the different file types. They compress the image data, and so take up less space on the camera’s memory card. Within the jpeg category there will be a choice of file sizes, ranging from high through normal to basic, with basic taking the least memory space of all. However, the saving in memory card space comes at the expense of loss of quality in the image.
Jpegs are lossy files – some of the information is lost as the image data is compressed, and also information is lost each time a jpeg is resaved.
Tiff files are lossless files, so all the image information is saved. The result is a much bigger file, which will take up more space on your memory card and also on your computer. Like jpegs, Tiff files are finished articles, with the chosen shooting parameters (such as white balance) already applied.
RAW files are the largest of all because they include all the unprocessed data from the sensor – unlike the other formats, RAW files are not finished articles, but are “undeveloped”. Because of this there is more flexibility to adjust the final image during computer processing. You’ll need some kind of RAW conversion software to read the RAW files – the camera manufacturers make their own, or you can get a RAW plug-in for Photoshop, Photoshop Elements or Lightroom.
If you only use your images for computer display, then jpegs are the quickest and easiest to use for emailing, or uploading to websites or facebook. If you want to make large prints though, then either Tiffs or RAW files will give you a better quality image.