  Measurements of Deeply Virtual Compton Scattering (DVCS) are presented using
data collected by the H1 and ZEUS experiments at HERA. The transition from a
virtual photon to an on-shell particle is expected to necessitate the use of
skewed parton distributions for a theoretical description. The results are
compared to theoretical predictions. Diffractive vector meson production
measurements from H1 and ZEUS are also presented in which the magnitude of the
four-momentum transfer squared |t| at the proton vertex is large. A large |t|
is expected to make it possible to perform a perturbative calculation. The
results are compared to recent theoretical predictions performed within the
framework of perturbative QCD.
