Metadata: What Is It?
“Metadata" might sound like a scary term, and a little bit magical, but it really isn’t. “Metadata" is just data about data, in this case, information about a picture that isn’t in the picture itself. For photography, this typically includes a time and date stamp, camera settings such as focal length, aperture and exposure, and the type of camera. For most cameras, this is recorded as an .exif, or exchangeable image file format. This file is embedded in with the .jpg, and indeed most image formats.
Why Edit Metadata?
There are few metadata editors out there. This is because many developers are uncomfortable with the idea of people editing their metadata. It’s easy to conceive of the deception arbitrary editing of metadata allows anyone to do, from stealing other people’s photos to creating illusions about when and where a picture was taken. Please think carefully before editing metadata: are you doing it for purposes of deception? Do you want to contribute to the distrustful mood surrounding many digital editing communities?
Including correct metadata with your photos can be a powerful tool, both for yourself and others. Knowing the time when a picture was taken can help you duplicate lighting conditions, for instance, and the date can help you remember what day precisely you made that Everest summit. Going back and critically looking through the camera settings and how it affected the final outcome of a picture can help you improve—looking to see which exposures created the best waterfall photographs, or which f-stops worked best for a flower macro. On many websites, such as DeviantArt, the metadata from your photos is included with the displayed picture, allowing other photographers to learn from your work as well. Knowing the metadata can be a powerful tool for improving photography—so making sure that it’s correct is of the utmost importance.
Before taking pictures with a camera, it’s a good idea to make sure that your time and date are set correctly: this is probably the most common reason why people feel the need to change the photo metadata on a given picture. For other settings, it might be a good idea to make sure that the .exif data is correct by taking a few test photos at known settings and checking the .exif data to see if it is reading correctly.
So, let’s say you need to edit your metadata. Not all major photo editing software have some sort of metadata editing capability already installed. Mac’s iPhoto is a conspicuous counterexample. However, for most programs, you may at least view .exif data, usually through a “file info" option. To see if your photo editing software has metadata editing capabilities, consult the relevant user guide.
As a result, most ways to edit metadata are a little more under the radar, created by independent developers. There are many lists of photo metadata readers, editors and extraction tools out on the internet, as well as general guides, from which you can select both free and propriety software and methods to suit your specific needs. Free software, terminal commands, plugins, methods abound, if you know where to look.