Digitally watermarking images
If you are publishing your images on the Internet you really should protect them in someway to ensure that someone else cannot easily steal your work.
In QuickTime movies, ImmerVision OpenPanorama (ivp) files, TIFF and JPEG files (as well as some other formats) you can add metadata information about the panorama (including copyright information) to the file. QuickTime metadata can be viewed with QuickTime Player and edited/created using QuickTime Pro as well as panoramic image stitching software that supports the full features of QuickTime. The OpenPanorama IVP format is an open standard and can also be edited using ImmerVision's PURE Tools
You will have seen metadata in JPEG files before - EXIF is a metadata standard for image files created by digital cameras (and other devices) and is added to JPEG or TIFF files. The standard was created by the Japan Electronic Industry Development Association. IPTC metadata is a standard created by the International Press Telecommunications Council in collaboration with Newspaper Association of America and this metadata can be added to JPEG and TIFF files. Adobe PhotoShop and other Adobe tools make it possible for you to define your own additional metadata that can be added to the IPTC comment field, but will not necessarily be correctly read/decoded by non Adobe software.
The simplest way to protect your work is to add a visible watermark to your images. If you are shooting spherical images the easiest way to do this is to add a tripod cap to hide the tripod. Alternatively, if you normally edit out the tripod completely, add your name/logo/copyright message to the ground where the tripod was. Personally I think a subtle embossed name/message on the ground looks cool.
In addition to visible watermarks and metadata, you can embed an invisible digital watermark into your images using solutions from Digimarc. A wide variety of software can read Digimarc watermarks including Adobe PhotoShop and then warn anyone viewing the image that it is copyright. Digimarc also provide services to search the Internet to check if your images are appearing anywhere you do not expect.
An invisible digital watermark involves rearranging the image pixels slightly to hide some information in the picture. If you set the watermarking to a very high durability the watermark will show up as a slight pixelation of the image. You can do a variety of changes to the watermarked image without affecting the watermark.