Posted 16 February 2009 - 11:39 AM
To be honest I had never heard of a SID file.
Wikipedia describes it as MrSID (pronounced Mister Sid) is an acronym that stands for multiresolution seamless image database. It is a file format (filename extension .sid) developed and patented by LizardTech for encoding of georeferenced raster graphics, such as orthophotos.
If you can view these files, you must have some software on your PC which recognises files with the SID file extension as versions of Windows do not support SID files. The chances are that the people you are sending this file to do not have a program on their PC which recognises the file format.
If you can view these files, you may have the option to save them in a different format. If you are able to do this, save them as a JPG file (which is supported in Windows) and then send that to your friends.