Image files hold hidden data about the file and the image itself

'The Kick' - image files store data about the file itself. See below for data in this image file.
Make - Canon Model - Canon EOS 5D Mark II
Orientation - Top left
DateTime - 2011:04:09 11:04:14
Artist - Damon Guy (Netkonnexion)
Copyright - Photokonnexion 2012
ExposureTime - 1/640 seconds
ISOSpeedRatings - 100
ApertureValue - F 4.00
Flash - Flash not fired
FocalLength - 280 mm
ExposureMode - Manual
White Balance - Manual
SceneCaptureType - Standard
The stored data is called EXIF, for Exchangeable Image File Format. The EXIF data is stored by a number of image formats including JPEG, JPG, Tiff, RIFF and WAV files as well as a number of Camera RAW formats from camera manufacturers. However, the EXIF data is not supported by JPEG2000, PNG or GIF image formats.
When you are learning photography the EXIF data is a great source of inspiration and information. It is inspiring because once you understand the EXIF data you can look at images produced by other photographers. Then you have an insight into the way they shot a particular image. If you spot a picture you like look at the EXIF data. You will be able to discern from the Shutter, aperture and ISO values some idea of what the photographer was doing to get that shot.
EXIF data is a great learning aid too. You can look at the EXIF data in all your own image files. Check out the settings at the time your shot was taken. If the shot did not go well you have a chance to analyze what went wrong. Next time you will know better.
EXIF data is readily available to you in a number of ways. You can get it from most image editor applications when you open your file. Irfanview, an image viewer and editor, has a dialogue box for reading and copying EXIF {press ‘altgr’ & ‘e’ together}. Photoshop and Elements have comprehensive read and edit tools for EXIF data. GIMP
has the same facility. To use these applications to see EXIF data you must consult the help pages for your version.
More after the jump…
You can also get the information from the EXIF data using Windows Explorer…
- Windows XP: Right click the image file; left click “Properties”; click the ‘Summary tab’; click the ‘Advanced button’
- Windows Vista/Windows 7: Right click the image file; left click “Properties”; click the ‘Details tab’
- Mac OS X: view EXIF data with ‘Finder’. Do a ‘Get Info’ on a file; expand the ‘More Info’ section
In some versions of Windows you can edit the EXIF data as well as read it. However, the data about the file itself remains in the file. You can remove the private data and edit the camera data. Although you can edit the information in Windows XP it is inadvisable as a bug sometimes corrupts the data in JPEG/JPG files.
Being able to edit the information for your EXIF file is useful as you might want to put additional data into the file that is not collected by your camera. For example you may want to put in contact details and copyright details. Alternatively you might want to remove some of the data. Some photographers do not publish EXIF data to prevent publishing information about the shot.
Every EXIF file supports fields that identify the data captured by the camera and which describe the file. Not all cameras support all fields. The EXIF format is a standard supported by at least the Japanese manufacturers, and many others too. It is also supported by some scanners although the EXIF standard does not cater for scanners.
Data from EXIF files may include camera data collected when the shot was taken. There is also copyright data you can edit in-camera or add during post-processing.
A number of applications are available for working with EXIF data. One example is EXIFTool which can edit fields of data in a comprehensive range of files and file types. However, this is quite a technical tool. You will need to be able to use the command line on a computer. If you cannot do that, then try using Irfanview described above. If you only want to read the EXIF information the you might try Exif Reader
.
Once you know about EXIF data and how to access it there are many ways to use the information. The first stage is to have a look at the data in your own image files carry. You can set up your camera so it will store your copyright information and other data in your images. You can also add other types of data beyond the pure EXIF data. Have fun with your data!














