Determine the size of an Image datatype

Is there any method to find out the size of an image datatype currently in the database. For example I have 2 tables that contain the same image, but the archive table is not displaying the same as the main. I am thinking the image file was corrupted somehow but don't know how to check this out.
Any ideas?DataLength() (http://msdn.microsoft.com/library/default.asp?url=/library/en-us/tsqlref/ts_da-db_4ep4.asp)

-PatP