H-alpha kinematics of S4G spiral galaxies-II. Data description and
  non-circular motions
  We present a kinematical study of 29 spiral galaxies included in the Spitzer
Survey of Stellar Structure in Galaxies, using Halpha Fabry-Perot data obtained
with the Galaxy Halpha Fabry-Perot System instrument at the William Herschel
Telescope in La Palma, complemented with images in the R-band and in Halpha.
The primary goal is to study the evolution and properties of the main
structural components of galaxies through the kinematical analysis of the FP
data, complemented with studies of morphology, star formation and mass
distribution. In this paper we describe how the FP data have been obtained,
processed and analysed. We present the resulting moment maps, rotation curves,
velocity model maps and residual maps. Images are available in FITS format
through the NASA/IPAC Extragalactic Database and the Centre de Donn\'ees
Stellaires. With these data products we study the non-circular motions, in
particular those found along the bars and spiral arms. The data indicate that
the amplitude of the non-circular motions created by the bar does not correlate
with the bar strength indicators. The amplitude of those non-circular motions
in the spiral arms does not correlate with either arm class or star formation
rate along the spiral arms. This implies that the presence and the magnitude of
the streaming motions in the arms is a local phenomenon.
