To add on to my post about orphaned worked I thought I might post some ideas and how-to's about watermarking and embedding tags in your photos.
One way is to use an invisible watermarking service like digimarc.
But it is expensive and requires a subscription.
So here are two ways that you can do it for free using my favorite little (and free) image utility, IrfanView.
The best way, and probably most interesting for a librarian, is to tag your photos with metadata. Images can have EXIF and IPTC data.
Using IrfanView, go to the thumbnails view - File > Thumbnails (or T)
Select all the photos you want to add data to. (You can hold down the Ctrl key or use shift for multiple selections)
Go to File > JPG Lossless Operations > Set IPTC Data to selected Files
Put in your various metadata. I recommend your name, website address if you have one, email address, year the photo was taken or the time of your last edit, and a message about your copyright or creative commons polices. There are many fields and you can enter lots of information if you wish.
Click Write - You're done!
This data is great to have in your photos and won't be visible and distracting when looking at it. Flickr can show this data. Theoretically if someone thought your photo was an orphaned work they would check this data and find out who you were.
This method is not without its flaws though. All you have to do is copy and past the photo and all of the information is gone. Even saving the photo from flickr on any of the different size views does not preserve the data. And, anyone can edit the photo and put their own data in. Still I think this is a good method to have your data in the photo initially.
You can watermark images the traditional way, which puts whatever little text you want directly on the image, and do it in batch.
Using IrfanView go to File > Batch Conversion/Rename (or B)
Click the advanced options checkbox and then click the corresponding button.
In the lower right click on "add overlay text" and then the corresponding settings button
put in your copyright info as you want it to appear, and where you want it to appear.
You may also want to click on "overwrite existing files" (if you trust yourself and don't want a backup) and "save files with original date/time" as well as making sure that nothing you don't want checked is checked. Click OK.
Now just add the images you want to watermark, make a note of where they will be saved, double check to make sure its right, and click "start batch." Voila! watermarked photos.
Personally I find this annoying looking, even if it is small, but getting rid of it is a bit of a pain, so it prevents theft. It is possible to remove them completely with Photoshop, especially if the text is on a plain background.
Here is a tutorial on more advanced watermark implementations that shows how to create them and how they can be removed. The end result is a photo you probably wouldn't want to look at anyway because it has a giant watermark on it.
There is actually a copyright tag in both EXIF and IPTC data, but it appears to only be used on flickr.
http://picurl.org/development/wiki/MetadataCategories - information about metadata tagging, EXIF and IPTC tags, and how they work on flickr.com and in Google Picasa
16 hours ago