The process of copying previously-burned DVD-R video discs doesn't work for copy protected DVDs. Disk Copy and Disk Utility are licensed only for reproduction of non-copyrighted materials. For Mac OS X 10.3 or later, you have to follow some extra guidelines to perform the task. For Mac OS X 10.2 through 10.2.8 and Mac OS X 10.0 through 10.1.5, the process is a bit simpler, but you need to follow the instructions step by step without skipping anything in order to accomplish your goal.
Save Time and Use Hinsdale DVD Duplication for the Best Results
Source:
http://support.apple.com/kb/HT2059
Save Time and Use Hinsdale DVD Duplication for the Best Results
Source:
http://support.apple.com/kb/HT2059
How to copy previously-burned DVD-R video discs
Learn how to use Disk Copy or Disk Utility to create a duplicate of a DVD-R video disc you previously made with iDVD or DVD Studio Pro if you no longer have the original source material to burn the project.
Note: This procedure will not work with copy protected DVD video discs. iDVD, DVD Studio Pro, Disk Copy, and Disk Utility are licensed for reproduction of non-copyrighted materials, or materials you are legally permitted to reproduce.
For Mac OS X 10.3 or later
1. Insert the DVD-R video disc that you created.
2. In the Finder, choose Utilities from the Go menu, then open the Disk Utility application.
3. Select the disc (not just the disc session) you want to copy from the listing on the left.
4. Sample selected disc
5. From the Images menu, choose New and then choose Image from "your disk name." (Mac OS X 10.4 and later: From the File menu, choose New and then choose Image from "your disk name").
6. Enter a file name and choose "DVD/CD Master" from the Image Format pop-up menu.
7. Click the Create button. After the image has been created you should see it in the 8. disk listing in the Disk Utility window.
9. Eject the DVD-R video disc.
10. Select the disk image you created from the listing.
11. Click the Burn icon in the toolbar.
12. When prompted, insert a blank DVD-R disc.
13. Click the Burn button.
Learn how to use Disk Copy or Disk Utility to create a duplicate of a DVD-R video disc you previously made with iDVD or DVD Studio Pro if you no longer have the original source material to burn the project.
Note: This procedure will not work with copy protected DVD video discs. iDVD, DVD Studio Pro, Disk Copy, and Disk Utility are licensed for reproduction of non-copyrighted materials, or materials you are legally permitted to reproduce.
For Mac OS X 10.3 or later
1. Insert the DVD-R video disc that you created.
2. In the Finder, choose Utilities from the Go menu, then open the Disk Utility application.
3. Select the disc (not just the disc session) you want to copy from the listing on the left.
4. Sample selected disc
5. From the Images menu, choose New and then choose Image from "your disk name." (Mac OS X 10.4 and later: From the File menu, choose New and then choose Image from "your disk name").
6. Enter a file name and choose "DVD/CD Master" from the Image Format pop-up menu.
7. Click the Create button. After the image has been created you should see it in the 8. disk listing in the Disk Utility window.
9. Eject the DVD-R video disc.
10. Select the disk image you created from the listing.
11. Click the Burn icon in the toolbar.
12. When prompted, insert a blank DVD-R disc.
13. Click the Burn button.