  The photoproduction of omega mesons off protons has been studied at the Bonn
ELSA accelerator from threshold to E_gamma = 1700 MeV. Linearly polarized beams
were produced via coherent bremsstrahlung. Large photon asymmtries in excess of
50% were obtained, whereas the pion asymmetries from omega \to pi^0 gamma are
close to zero. The asymmetries do characteristically depend on Theta_{cm}
rather than |t| and indicate s-channel resonance formation on top of t-channel
exchange processes.
