Know your digital image file extensions and how to use them?

Understanding the file extensions on digital images is a fundamental skill for managing your digital images. The most commonly used digital image file extensions are:

•   .jpg
•   .tif
•   .gif
•   .raw
•   .psd

Immediately below are definitions for these terms borrowed from the Professional Guidelines document, Working With Digital Images Effectively.

JPEG is usually shown as  .jpg and .jpeg on your digital image file names.
JPEG is a file extension used specifically for images.
JPEGs are compressed images and consequently smaller files.
JPEGs can contain millions of colors.
RECOMMENDED APPLICATION: JPGs are good for emailing images because they are smaller files.  JPG is also ideal to upload to social networking sites such as Facebook or Crafthaus.  The compressed image files are ideal for these applications because they use less file storage space.
CONCERNS: Do not send JPG images for print media such as books or magazines. The compression of the images compromises the quality of the print image.

TIFF is shown as .tif and .tiff on your digital image file names.
TIFF is a file extension used specifically for images.
TIFFs are uncompressed image files and thus are larger.
TIFFs can contain millions of colors.
RECOMMENDED APPLICATION: TIFF is an excellent format for print-quality 300 dpi images. The large file size is usually too large for email.  Instead, burn your TIFFs on a disc or USB drive and mail them (the old fashioned snail mail way) or use a file uploading service such as Dropbox.com or Hightail.com

California Dream Teapot
Photo Credit: Philip Cohen

GIF is shown as .gif at the end of your digital image names.
GIF is a file extension used specifically for images.
GIFs are compressed image files.
GIFs contain only 256 colors.
RECOMMENDED APPLICATION: GIFs are the only extension that supports animated images which may include multiple or automated imagery. What is an animated image? It is just like the image to the right. 

PSD is shown as .psd at the end of your digital image names.
PSD is a file extension for images used only in Photoshop.
PSDs are uncompressed image files.
PSDs can contain multiple layers and millions of colors.
RECOMMENDED APPLICATION: PSD is a file extension for images that can save all your graphic design work and layers for future editing.
CONCERNS: The problem with sending PSD images to other people is that the images are usually too large to email and the recipient can only open a PSD file if they have Photoshop or a compatible photo editing software on their computer.  Not everyone owns Photoshop or photo editing software, so check in advance before sending a PSD to anyone (including magazine and book editors).

RAW is shown as .raw at the end of your digital image names.
RAW image files contain the actual data captured by the camera sensor without any in-camera processing; these are the only files containing “pure” data. Working with camera RAW files gives you maximum control; you can set the white balance, tonal range, contrast, color saturation, and sharpening. Think of camera RAW files as your photo negative or original slide. You can reprocess the file at any time in Photoshop or image editing software to achieve the results you want. To create RAW files, you need to set your camera to save files in its own RAW file format.  RAW creates the largest possible image file in your camera.

RECOMMENDED APPLICATION: Book publishers often ask for RAW files to avoid amateur (poor quality) Photoshop modifications.
CONCERNS: The problem with sending RAW images to other people is that the images are usually too large to email and the recipient can only open a RAW file if they have Photoshop or a compatible photo editing software on their computer.  The professional photographer that I use to photograph my work will not send RAW images, but he will send TIFFs.

Hope this information helps you understand digital images better. It takes a little practice to understand digital images but this is the future, so don't resist learning digital technologies. If I can learn this, anyone can.

Harriete

This post was updated on December 22, 2021, to provide current links.