Doing a low-level disk clone with
dd from a larger disk to a smaller one is very likely to result in lost data. Any files that happened to be stored after the 480GB mark on your source disk will now be lost on your 1TB target. Thus, the best way to do the job is to use another utility. Offhand, I don't know of any Linux utilities that will do this job for NTFS (IIRC,
ntfsclone requires that the target be at least as large as the source). I'm sure there are Windows backup utilities that will do the job. I've used XML Backup once or twice in the past, but it's been a while, so I'm not sure how well it would handle your situation. Alternatively, you could use
ntfsresize to shrink the source filesystem before cloning the disk with
ntfsclone. Be aware, though, that filesystem resizing tools always pose a risk; you could end up losing data in your effort to clone the filesystem.
I don't know offhand how
ntfsresize or similar utilities will react to a filesystem that's larger than the containing disk. They might work, or they might crash or even damage the filesystem. Thus, to be safe, I recommend going back and doing it again in a more appropriate way.