A new method was developed to acquire images automatically at a series of specimen tilts,
as required for tomographic reconstruction. The method uses changes in specimen position
at previous tilt angles to predict the position at the current tilt angle. Actual measurement of
the position or focus is skipped if the statistical error of the prediction is low enough. This
method allows a tilt series to be acquired rapidly when conditions are good but falls back
toward the traditional approach of taking focusing and tracking images when necessary. The …