  In a neutral particle gas detector, the parallax error resulting from the
perpendicular projection on the detection plane or wire of the radial particle
trajectories emanating from a point like source (such as a scattering sample)
can significantly spoil the apparent angular resolution of the detector.
However, as we will show, the information is not lost. We propose an off line
data treatment to restore as much as possible the original scattering
information in the case of a one-dimensional parallax effect. The reversibility
of parallax follows from the algebraic structure of this effect, which is
different from the resolution loss which is essentially irreversible. The
interplay between finite resolution and parallax complicates the issue, but
this can be resolved.
