If you imaged the whole drive you can use offset option with mount command. mmls (from The Sleuth Kit) can show partitions within an image
$ mmls image -b
DOS Partition Table
Offset Sector: 0
Units are in 512-byte sectors
Slot Start End Length Size Description
00: ----- 0000000000 0000000000 0000000001 0512B Primary Table (#0)
01: ----- 0000000001 0000000031 0000000031 0015K Unallocated
02: 00:01 0000000032 0001646591 0001646560 0803M DOS FAT16 (0x06)
03: 00:00 0001646592 0002013183 0000366592 0179M DOS FAT16 (0x06)
Mount the DOS partition starting at block 32:
sudo mount -o loop,offset=16384 image mnt
(32 multiplied by 512 byte blocks = 16384)
For mounting a typical NTFS partition created by Windows use:
sudo mount -t ntfs -o r,force,loop,offset=32256 image mnt
(63 multiplied by 512 byte blocks = 32256)