cgsecurity.org

I have been making an image of a 1 TB drive for about a day and a half now, and just realized that the image file is not getting any larger. Testdisk just hit 26% and my image file is only 6.7 GB. Could it be skipping empty space? The drive was only about 15% full and it seems like empty space would go by quicker... IDK

I'm wondering if I should wait 3-4 more days for this to finish, or if I need to go about this some other way?

Thanks in advance

The image.dd file should grow if testdisk is able to read data (including only zero) from the source disk.
To deal with large disk or with badly damaged disk, it's recommended to use ddrescue as explained in https://www.cgsecurity.org/testdisk.pdf