Both command-line and screen-oriented pointers appreciated!
update:
I verified the disk utility, hdiutil, and dd methods. dd seems the fastest, 30 minutes on my macbook pro vs. 40 minutes for hdiutil. I was able to simplify dd to use just if= and of=
For the DVD, I used /dev/disk2. I verified this with diskutil list and unmounted it first.
$ sudo umount /dev/disk2$ dd if=/dev/disk2 of=mydisk.iso
