Image size for bitlockeree SSD

[Gordon2M]

I have been imaging a system SSD using TBWinre and I am puzzled about the size of the resulting image, The drive in question is a nominal 512GB. When the imaging starts, the indication is that something over 900GB are to be processed (this is with byte-for-byte validation). Around 250GB of the SSD is used. The resulting .TBI image file has a size of around 220GB.

My (perhaps mistaken) understanding is that images of bitlockered drives are not compressed, so I was expecting that the filesize of the TBI file would be around the full size of the SSD.

Could someone explain why the image size is smaller than I expected.

I am using Windows 11 Home.

Thank you.
Gordon

[Brian K]

Gordon, how are you unlocking the OS partition in TBWinRE? Are you using Read from Volume in IFW?