  The explicit procedures are described for reconstruction of the full set of
helicity amplitudes in proton-proton and proton-antiproton elastic scattering.
The procedures are based on the derivative relations for the helicity
amplitudes in s-channel, on the explicit parametrization of the leading spin
non flip amplitudes and crossing - symmetry relations. Asymptotic theorems are
used for definition of free parameters in derivative relations. We also study
the Odderon influence on the helicity amplitude reconstruction. Reconstruction
procedures are valid at extremely wide energy domain and broad range of
momentum transfer. These procedures might be useful in studying the spin
phenomena in proton-proton and proton-antiproton elastic scattering.
