Just some terminology... as mentioned previously, the images are copyrighted the moment you take them. You writing something on them is helpful to scare away a thief. If you actually are concerned about future enforcement of a copyright, then you *register* it. In the USA that's with www.copyright.gov
I gave my first best answer for this. Getting confirmation that CT will be here for the near future is one of the best gifts I could ask for this holiday season. Thank you, Peter, you run a great show...and thanks to all moderators and supporters, too. Finally, thanks to the great members on the forum who have shared their knowledge and wisdom. (“likes” not required, that is not my intention)...Spark
A number of my photos posted on CoinTalk have found their way to other websites & Google without my permission & couldn't care less, actually it flatters me ! If anyone can make money using my photos that wouldn't bother me either .
Typically (when I'm not being lazy), I put a notice in the EXIF data... "Copyright (C) 20xx, name, all rights reserved except permission is granted to republish for numismatic purposes."