Why bother?
The unfortunate reality of the Web is that there are unscrupulous people who will lie, cheat and steal in their pursuit of online success.
Nothing is sacred.
Those who sell (or license) their images online need a way to protect them from theft.
Those who don't profit from their photos may also want to keep their work from being copied, and their talent exploited.
While there are several ways to protect images (transparent gifs, disabling right click), none of them are completely reliable, and each approach has it's disadvantages.
Watermarking can be cropped out if it's restricted to the bottom or corner of the photo. So a more prominent mark is necessary, which can interfere with the appearance of the photo.
Finding a balance is key. The photo shouldn't be compromised so much that it's destracting to your visitors but enough that it dissuades would-be thieves.
Try the following method to create a nice transparent watermark on your photos (see example image below). It's done using the free graphic software, Paint.NET, which can be downloaded here.
Once you've downloaded the software, you'll need an image to overlay on your photo. The graphic you choose could be...
Most important is that you choose a simple graphic on a white background.
After you've got your copyright image saved and ready to go follow these steps...
1) Open paint.NET and from the File menu, select Open and open up the image you want to watermark.
2) Once you have the image opened, go to the Layers drop down menu (in the top bar) and select Import From File
3) Locate your copyright image that you wish to watermark onto the photo. Don't worry that it's on a white background, there's a magic button to make it transparent... later.
4) Once you've imported that image onto your original, go to the Tools menu (on the left) and click on the upward pointing arrow to Move Selected Pixels. Then put your cursor on the imported image and move it to where you want it on the photo.
5) Go to the Effects menu in the top bar and choose Emboss. It'll turn grey... no worries. At this stage you can play with the angle a bit until you're happy with where the highlights are placed. Then click OK.
6) Go back to the Layers menu and select Layer Properties. From the drop down menu, choose Overlay and adjust the opacity to a level that works well with your image. Click OK.
7) Go to the Image menu in the top bar and select Flatten. Presto! You've got a transparent version of your copyright symbol overlayed on your image.
At the right is a sample of what a watermarked image looks like using this method.
The mark will be more visible on some images than others. It just depends on the colors and amount of activity in the image.
You can adjust the level of embossing and the opacity to make the overlayed image stand out more or less as desired.