NetRestore Helper provides NTFS partition imaging if the ntfsprogs are installed. A couple of important points to make:
1) NetRestore Helper will not image a partition on the same physical device as the running OS. That is, if you have a BootCamp-ed drive and are running Mac OS from that internal drive, you will NOT be able to create an image of the Windows partition. Rather, you should have an external drive with a bootable Mac OS on it. Boot into that (external) OS, which has NetRestore Helper and ntfsprogs installed. You should be able to image the (internal) partition containing Windows.
HOWEVER
2) There is a conflict between ntfsprogs and NTFS-3G (which you may have installed to read/write to your Windows partition). SO, on the external drive, make sure you only have the ntfsprogs installed. NetRestore Helper will not use the NTFS-3G driver to work its magic.

Also, for the sake of my own documentation, the following is from the provided ntfsprogs docs.
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The following utilities are so far implemented:
ntfsfix - Attempt to fix an NTFS partition and force Windows to check NTFS.

mkntfs - Format a partition with the NTFS filesystem. See man 8 mkntfs for command line options.

ntfslabel - Display/change the label of an NTFS partition. See man 8 ntfslabel for details.

ntfsundelete - Recover deleted files from an NTFS volume. See man 8 ntfsundelete for more details.

ntfsresize - Resize NTFS volumes. See man 8 ntfsresize for details.

ntfsclone - Efficiently create/restore an image of an NTFS partition. See man 8 ntfsclone for details.

ntfscluster - Locate the owner of any given sector or cluster on an NTFS partition. See man 8 ntfscluster for details.

ntfsinfo - Show some information about an NTFS partition or one of the files or directories within it. See man 8 ntfsinfo for details.

ntfsls - List information about files in a directory residing on an NTFS partition. See man 8 ntfsls for details.

ntfscat - Concatenate files and print their contents on the standard output.

ntfscp - Overwrite files on an NTFS partition.

ntfsmount - Mount an NTFS partition from user-space using libntfs and FUSE.