The Value contains a constant or expression that evaluates to the location of the image. This can be a full folder path (for example, “/images/logo.gif”), relative path (for example, “logo.gif”) or URL (for example, “http://reportserver/images/logo.gif”). Relative paths start in the same folder as the report.
The Value contains a constant or expression that evaluates to the name of an EmbeddedImage in the report.
The Value contains an expression (a field in the database) that evaluates to the binary data for the image.