  The two-dimensional sub-cycle-time to electron momentum mapping provided by
orthogonal two-color laser fields is applied to photoelectron spectroscopy.
Using neon as the example we gain experimental access to the dynamics of
emitted electron wave packets in electron momenta spectra measured by
coincidence momentum imaging. We demonstrate the opportunities provided by this
time-to-momentum mapping by investigating the influence of the parent ion on
the emitted electrons on laser-sub-cycle times. It is found that depending on
their sub-cycle birth time the trajectories of photoelectrons are affected
differently by the ion's Coulomb field.
