Now that I have explained the different types of image metadata there is one more question to answer: how does this image metadata end up in your image files? This article will explain the road very frequently traveled by image metadata. From your camera to your computer and back to your image file, image metadata becomes connected to each image and this way becomes PORTABLE.
From camera to the memory card.
When you take a picture, the image pixels are being saved to the memory card by your camera. In addition, your camera attaches EXIF information to each image file that it saves. Technical information like: camera model, ISO value and aperture value are saved along with each image. This way you can see all this information when you view each image in your software.
The road traveled by image metadata from camera to computer
From memory card to computer.
Nothing really happens here other than EXIF information traveling with your images to your computer. Now YOU get to add more metadata to your images. This time however, the information you create has to to with the content of each image (i.e. keywords, location). You, as the author of the image are the only person that can create this information. This is where you rely on your imaging software to help you create content information like keywords (or tags). Keywords are part of the IPTC and XMP standards and they represent content information and not technical information. Sorry for repeating that so many times…but it’s important.
From image software back to the image file.
Depending on your software, you can create IPTC or XMP or both types of image metadata. Once you create them in your software you can save them to the image file itself. Now, your image file will have multiple layers of metadata (EXIF, IPTC and XMP). This way you metadata is connected to each image file itself making image metadata PORTABLE.
The goal of creating image metadata is to attach it to each image file. This way image metadata can travel with your pictures wherever you want to send or store them. The ultimate goal for image metadata is PORTABILITY.
Important note. The file formats that support embedded metadata are JPG and TIFF on the compressed side and DNG on the raw side. If you are using a proprietary raw format, then it is up to your software to embed metadata in a side file which you have to be very careful about so not to lose them.
Beware of software that does not support image metadata portability.
I would add one important feature that you want to check before buying photo management software. You have to make sure that the software will be able to transfer your keywords to the actual image file. NOT ALL photo management programs offer this feature…so you have to read the manual of the software. For example ACDSee Photo Manager version 10 will allow you to create keywords but you will NOT be able to save them to your image files in IPTC. You would have to buy the Pro version in order to accomplish this task.
In order to achieve PORTABILITY of your image metadata you have to make sure your software supports writing IPTC/XMP fields. You have to specifically instruct your software to save the keywords you create. Some programs allow you to automatically save keywords to your image files but you would have to specify which formats you would want to use.