  We present the very first wide-field, 11 by 11 arcmin, optical spectral
mapping of M16, one of the most famous star-forming regions in the Galaxy. The
data were acquired with the new imaging Fourier transform spectrograph SITELLE
mounted on the Canada-France-Hawaii Telescope (CFHT). We obtained three
spectral cubes with R=10'000 (SN1 filter), 1500 (SN2 filter) and 600 (SN3
filter), centered on the Pillars of Creation and the HH216 flow, covering the
main optical nebular emission lines: [O II]3726,29 (SN1), Hb, [O III]4959,5007
(SN2), [N II]6548,84, Ha, and [S II]6717,31 (SN3). We validate the performance,
calibration, and data reduction of SITELLE, and analyze the structures in the
large field-of-view in terms of their kinematics and nebular emission. We
compared the SITELLE data to MUSE integral field observations and other
spectroscopic and narrow-band imaging data to validate the performance of
SITELLE. We computed gas-phase metallicities via the strong-line method,
performed a pixel-by-pixel fit to the main emission lines to derive kinematics
of the ionized gas, computed the mass-loss rate of the Eastern pillar (the
Spire), and combined the SITELLE data with near-infrared narrow-band imaging to
characterize the HH216 flow. The comparison with previously published fluxes
demonstrates very good agreement. We disentangle the dependence of the
gas-phase metallicities (derived via abundance-tracing line ratios) on the
degree of ionization and obtain metallicities that are in excellent agreement
with the literature. We confirm the bipolar structure of HH216, find evidence
for episodic accretion from the source of the flow, and identify its likely
driving source. We compute the mass-loss rate of the Spire pillar on the East
side of the H II region and find excellent agreement with the correlation
between the mass-loss rate and the ionizing photon flux from the nearby cluster
NGC6611.
