  The (\pi^{-}\Delta^{++}) production on the nucleon by real and virtual
photons is discussed as initial step in a simple model approach for the two
pion photo- and electroproduction on the nucleon, with emphasis on nucleon
resonance excitation which is of interest for new facilities like TJNAF. A
calculation for (\pi^{-}\Delta^{++}) channel in resonance excitation region is
presented and compared to existing experimental data along with a discussion of
physical effects that we find to be of relevance. The calculation is proposed
as a starting basis for the investigation of (N^{*}) electromagnetic form
factors using experimental data about two pion production by real and virtual
photons.
