ddrescue

ubuntu@ubuntu:~$ sudo ddrescue -b 4096 -d -f  /dev/sda /dev/sdc3 rescue.log
GNU ddrescue 1.22
     ipos:  233302 MB, non-trimmed:        0 B,  current rate:  84082 kB/s
     opos:  233302 MB, non-scraped:        0 B,  average rate:  83651 kB/s
non-tried:  266974 MB,  bad-sector:        0 B,    error rate:       0 B/s
  rescued:  233302 MB,   bad areas:        0,        run time:     46m 29s
pct rescued:   46.63%, read errors:        0,  remaining time:         43m
                              time since last successful read:          0s
Copying non-tried blocks... Pass 1 (forwards)