Due to observational constraints, dark matter determinations in nearby
clusters based on weak lensing are still extremely rare, in spite of their
importance for the determination of cluster properties independent of other
methods. We present a weak lensing study of the Coma cluster (redshift 0.024)
based on deep images obtained at the CFHT. After obtaining photometric
redshifts for the galaxies in our field based on deep images in the u (1x1
deg2), and in the B, V, R and I bands (42'x52'), allowing us to eliminate
foreground galaxies, we apply weak lensing calculations on shape measurements
performed in the u image. We derive a map of the mass distribution in Coma, as
well as the radial shear profile, and the mass and concentration parameter at
various radii. We obtain M_200c = 5.1+4.3-2.1 x10^14 Msun and
c_200c=5.0+3.2-2.5, in good agreement with previous measurements. With deep
wide field images it is now possible to analyze nearby clusters with weak
lensing techniques, thus opening a broad new field of investigation