You don' need to put anything on the image to have copyright apply in the US, you *do* need to register the image with the copyright office if you want putative damages available against infringers.
Note that watermarking images affects sales very heavily if its done in a way that can't simply be cropped or healing brushed out.
IMO, you're better off putting small low-res samples up online than trying to watermark.
Correct. This is actually a large misconception in terminology. You cannot simply put the copyright symbol on your images and call them copy-written. It has to be registered with the copyright office to be considered that.
What we photogs do is watermark our images, and that is just creating proof that we have the original image on file... original being one with the most information. Since you can't un-crop an image that isn't an original, putting the WM on the bottom (preferably) or in the center (amateur) is one way to insure that you will have the original.
Thanks for the lo-res idea. I didn't really think about that.
Not too many people do. It's a learning experience. It's honestly the best way to put your best image forward, not come off as a snobbish shooter, and still protect your image.
Another way is to add a comment to the image via the camera you use. My comments are my name, and they are imbedded in every image I shoot, and can't be changed easily. Aperture and Lightroom (as far as i know) can't view image comments, only in Photoshop. But you can add them to every image automatically.
That, and the low res upload is how I protect my images, but for the most part, the 100% best way to do so is to not put them online. Once they are online, it's far game as long as no one claims them as their own, or gains any monetary value from the use of your image.
For the last several months I've been putting a small copyright notation in the lower right of any images I post online. The reason is I've run into one or two instances where someone took and used some of my material on their own site, without asking and without attribution..
The sad truth is they don't have to. As long as they aren't making any money directly from the image, or they aren't claiming the image as their own creative work, they can post your image wherever they want too. (more technical stuff there though, like subject image portrayal etc.)
Even if they take your image and use it in a collage they are free to do so. OR, if they clone/airbrush/crop out your copyright, and edit the image to the point where the original intent is lost they are fine.
Putting up low res images is a bit more elegant because the artist can't blow up the image without destroying the quality/clarity of the photo. Or tying it to the website via flash or HTML, and stripping the metadata from it.