Q: I try to keep my digital photos organized in folders on my hard drive but it’s difficult for me to always find the image I’m looking for. What is tagging and how can it help me? Are tags the same thing as metatags?

A: Yes and no. When it comes to the realm of digital photography, tags, or metadata tags are simply labels that you apply to digital images using special software such as Picasa or iPhoto (or Lightroom or Aperture or many other programs).

Do not confuse these terms with their usage in the context of Search Engine Optimization (SEO), where “meta tags”, “keywords” mean very different things — and thus should not be confused with their meaning in digital photography.

Using metadata to help manage your digital photography library makes it easier to find the images you are looking for. Note that within the broad concept of “metadata” there are many fields you can populate with data: keywords, event, date, author, and rating are all examples of metadata. If you’ve ever looked at a digital image in Picasa and saw some information on the side about your camera or the settings (e.g iso, focal length), then you are actually looking at metadata. The iso setting or focal length information isn’t metadata you’d need to edit, but the keywords are an example of metadata you would want to edit. Now this isn’t an exhaustive list of what fields are available for you to use within the set of metadata, but the take-home message here is that metadata allows you to identify, organize and categorize your digital images as generally or as specifically as you want.

And when someone uses the word “tag” or talks about “tagging” your photos, they are talking about adding metadata to the image — usually in the form of adding keywords to an image.

Let’s look at an example using only metadata keywords (which is a great start).

Consider the following folder setup on your hard drive:

/Photos
/Vacations
/Florida_05
/Florida_08
/Paris
/London
/New_York_06
/New_York_07

If you want to see all of the pictures that were taken on your trip to New York in 2006 you could easily browse to the /New York folder and see the images. And if you wanted to see all of the pictures from your tip to new your in 2008 you could browse that folder, too.

But what if you wanted to see all of the pictures from both of your New York trips at the same time?
What if you wanted to see all of the pictures from Europe at the same time?
What if you only wanted to see pictures that included the kids?

With the above folder structure — by just using files and directories — you can’t. All you could do is browse through the folders and look through each image to see what you wanted to find. So to see all of the Europe photos you’d need to look in the Paris and London folders.

This is where metadata becomes really useful. Now know that you cannot tag (label) an image through Windows, meaning you can’t go to My Documents and then to My Pictures and somehow apply tags to the image files. To apply tags to an image file you need to be using a program that supports tags. Almost every digital photo management program provides for some level of tagging. Whether you are using Picasa or iTunes (Mac only), Lightroom or Aperture, all of these programs allow you to tag (label) your files.

So if you were using Picasa or iPhoto, for example, you could easily browse all of your photos and easily select the ones that were taken in London and Paris and then label all of these photos with the tag “Europe”. In this example when I say “tag” I am talking about using keyword tags — remember that there are many different types of tags in the metadata scheme and the keyword is one of those tags. Similarly, you could browse your photo collection and select all of the pictures that include your children and assign the keyword “kids”. Now if you wanted to find all of the photos of Europe, you could search (in Picasa or iPhoto [or whatever program you are using]) using the “Europe” keyword and all of your photos with the “Europe” keyword will show up.

What’s even more exciting about tags is that you can apply multiple keywords (or any meta tags) to an image. So let’s say you have the “Europe” photos selected. You can browse through these images, find the ones with the kids, and the apply the tag “Kids”. So now you have images that are tagged with the labels “Europe” and “kids”. So as you can see, the tagging possibilities are endless and you are only really limited to the amount of detail that you want to incorporate. The more tags you have applied to your images, the more fine-tuned searching you can do.

Now briefly…another type of metadata is the “rating” or tag. Some of the photo programs support this tag so not only can you have an image with multiple keyword tags (Europe, Kids) but you can also have a ratings tag. So now you could see all of the photos that are from Europe, show the kids, and have a 4 star rating.

Caveats
1. Not all programs work with the same metadata information — some programs have proprietary tags or limited tagging features.   Picasa has its own keyword system that is not usable outside of Picasa.  So if you really want to get involved in metatagging your photos, Picasa probably isn’t the product for you.  Simillarly, Expression Media 2 has certain metadata items that are specific to this program only and these specific fields will not be recognized by other programs.

2. Think about using  .DNG .DNG is an open-source file format that has the ability to store the met data within the file itself.