The IPHAS-POSS-I proper motion survey of the Galactic Plane
  We present a proper motion survey of the Galactic plane, using IPHAS data and
POSS-I Schmidt plate data as a first epoch, that probes down to proper motions
below 50 milliarcseconds per year. The IPHAS survey covers the northern plane
($|b| < 5^{\circ}$) with CCD photometry in the $r$, $i$ and H${\alpha}$
passbands. We examine roughly 1400 sq. deg. of the IPHAS survey area and draw
up a catalogue containing 103058 objects with significant proper motions below
150 millarcseconds per year in the magnitude range 13.5$< r' <$19. Our survey
sample contains large samples of white dwarfs and subdwarfs which can be
identified using a reduced proper motion diagram. We also found several objects
with IPHAS colours suggesting H${\alpha}$ emission and significant proper
motions. One is the known cataclysmic variable GD552; two are known DB white
dwarfs and five others are found to be non-DA (DB and DC) white dwarfs, which
were included in the H$\alpha$ emission line catalogue due to their lack of
absorption in the H$\alpha$ narrow-band.
