  Lattices in three dimensions are oft studied from the ``reciprocal space''
perspective of diffraction. Today, the full lattice of a crystal can often be
inferred from direct-space information about three sets of non-parallel lattice
planes. Such data can come from electron-phase or Z contrast images taken at
two tilts, provided that one image shows two non-parallel lattice
periodicities, and the other shows a periodicity not coplanar with the first
two. We outline here protocols for measuring the 3D parameters of cubic lattice
types in this way. For randomly-oriented nanocrystals with cell side greater
than twice the continuous transfer limit, orthogonal +/-15 deg and +/-10 deg
tilt ranges might allow one to measure 3D parameters of all such lattice types
in a specimen from only two well-chosen images. The strategy is illustrated by
measuring the lattice parameters of a 10 nm WC_{1-x} crystal in a
plasma-enhanced chemical-vapor deposited thin film.
