  The exclusive diffractive production of vector mesons and real photons in ep
collisions has been studied at HERA in a wide kinematic range. Here we present
the most recent experimental results together with a Regge-type model. We
deduce the Pomeranchuk trajectory (Pomeron) by analyzing the HERA data on
deeply virtual Compton scattering (DVCS), and then discuss its basic
properties, namely its apparent "hardness" and its "non-flat" behavior,
different from the claims of some authors.
