If you copy images with dd (DiskDump) you never know how much is already copied.
There are now progress bars or status messages but you can get these information easily.

Goto the terminal which executes dd and open a new tap or shell and enter:
ps -ax | grep dd
Now you see the PID of the dd process. Enter these PID in the following command and see what happens
(sudo) kill -USRSIG1 PID
In your dd terminal are now further information about the copying process.