  The new planet finder for the Very Large Telescope (VLT), the
Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE), just had its
first light in Paranal. A dedicated instrument for the direct detection of
planets, SPHERE, is composed of a polametric camera in visible light, the
Zurich IMager POLarimeter (ZIMPOL), and two near-infrared sub-systems: the
Infra-Red Dual-beam Imager and Spectrograph (IRDIS), a multi-purpose camera for
imaging, polarimetry, and long-slit spectroscopy, and the integral field
spectrograph (IFS), an integral field spectrograph. We present the results
obtained from the analysis of data taken during the laboratory integration and
validation phase, after the injection of synthetic planets. Since no continuous
field rotation could be performed in the laboratory, this analysis presents
results obtained using reduction techniques that do not use the angular
differential imaging (ADI) technique. To perform the simulations, we used the
instrumental point spread function (PSF) and model spectra of L and T-type
objects scaled in contrast with respect to the host star. We evaluated the
expected error in astrometry and photometry as a function of the signal to
noise of companions, after spectral differential imaging (SDI) reduction for
IRDIS and spectral deconvolution (SD) or principal component analysis (PCA)
data reductions for IFS. We deduced from our analysis, for example, that
$\beta$Picb, a 12~Myr old planet of $\sim$10~\MJ and semi-major axis of 9--10
AU, would be detected with IRDIS with a photometric error of 0.16~mag and with
a relative astrometric position error of 1.1~mas. With IFS, we could retrieve a
spectrum with error bars of about 0.15~mag on each channel and astrometric
relative position error of 0.6~mas. For a fainter object such as HR8799d, a
13~\MJ planet at a distance of 27~AU, IRDIS could obtain a relative astrometric
error of 3~mas.
