Images containing
only a few unit cells are not suitable to average in reciprocal space via
Fourier transform. VEC provides a direct-space translational averaging.
Specify the
three corners of a parallelogram which corresponding to an arbitraryly
positioning unit cell. For specifying each corner, bring the cursor to
the desired position, then click the button 
, input the coordinates in the dialog box and click 'OK'.
After defining
a unit cell on the image, click the button 
, the image intensity on each pixel will then be averaged with its unit-cell
translational equivants. The result will be in a new sub window
as seen on the right of the figure below. The green lines are unit cell
borders which can be shown or hid using the corresponding function in the
"Image" pulldown menu.
The resultant
image (on the right of the above figure) of cell averaging can now be improved
by reciprocal-space symmetry averaging. Simply click on the window (let
it be the current window) and then click the button
.
For details see the next section.