Create ISO **FROM** CD (**NOT** burn ISO back to useable CD) ??

Well, in the case of your OS X disk, a DVD is what the new disk would have to be, not a CD. And a dual layer DVD at that.

You also do use Disk Utility for this. Launch the app and put the disk you want to image in the drive. Select it at the left. Along the top row, click on the New Image icon. Under Image Format on the resulting sheet, choose DVD/CD Master. Give it a name and click Save.

Insert a blank disc.
Start Disk Utility.
From the File menu, choose Open Disk Image and select the ISO to be burned.
In the list of volumes, you will now see an item representing the ISO file. Select it.
Click the Burn button and follow the instructions.


ok im kind of a noob here how do i i create y own post

Yes, the extension is .CDR, but it doesn't really have anything to do with a CD in particular. It's an exact copy of the contents of whatever disk you create the file from. It doesn't have a .ISO extension, but it's the same thing.

Whether or not you could just change the extension and have it work, I don't know, but there's no need to do that. Unless you were to try and use the file on a PC to create a new disk and would have to change it in order for the software you use there to recognize the file as a disk image. On the Mac, you would just use it as is to burn your duplicate.