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\end{figure}  %  For the object classification in stars, galaxies and false detections,  we considered a similar analysis as Bardeau\,et\,al.\,2005, taking into account the position of the source in the magnitude/central flux diagram, the FWHM respect to the seeing and the stellarity index, according to the CLASS\_STAR parameter. Objects that are more sharply peaked than the PSF (FWHM replace_contentlt;$ $<$  \textit{seeing} - 0.5 pixel) and with FLAG parameter replace_contentgt;$ $>$  4, are considered as false detections. As the light distribution of a point source scales with magnitude, objects on the line magnitude/central flux, $\pm$ 0.4 magnitudes (Figure\,\ref{sources}), FWHM replace_contentlt;$ $<$  \textit{seeing} + 1 pixel and CLASS\_STAR replace_contentgt;$ $>$  0.8 are considered as stars. The rest of the objects are considered as galaxies. \\ %  \subsection{Shape measurements}  % 

\subsection{Background Galaxies selection and redshift distribution}  %  Background galaxies for the shear estimation, were selected as the galaxies with magnitude in the filter \textit{r'}, $m_{r}$, higher than $m_{L}$, and lower than $m_{max} + 1.0$, where $m_{L}$ is defined as the lowest magnitude $r'$ such that the probability that the galaxy is behind the cluster is higher than 0.7 and $m_{max}$ correspond to the peak of the magnitude distribution of the image in the filter \textit{r'} (both magnitudes for each cluster are listed in Table\,\ref{table:2}). The later cut in magnitude ensures that we are not taking into account galaxies that are too faint, given that they could have great errors in the shape measurements. Also, as we did for the simulated data, we discard galaxies with FWHM replace_contentlt;$ $<$  5, with companions closer than 16 pixels and with $\sigma_{e} > 0.2$.\\ To compute $m_{L}$ we used the catalogue of photometric redshifts computed by Coupon et al. 2009, based on the public release Deep Field 1 of the Canada-France-Hawaii Telescope Legacy Survey. We estimated the fraction of galaxies with $z > z_{cluster}$ in magnitude bins for the \textit{r'} filter, and then we chose $m_{L}$ as the lowest magnitude for which the fraction of galaxies was greater than 0.7. Background galaxy density after the selection are listed for each cluster in Table 2.\\  Once we obtained a catalogue for the background galaxies, we average the two components of the ellipticities (E-mode and B-mode) in nonoverlapping logarithmic annuli, to conserve the S/N ratio in each bin. In order to take into account the contamination of foreground galaxies in the catalogue, we weighted the average value of the components of the galaxie's ellipticity with the probability that the galaxy was behind the cluster. We compute this probability using Coupon's catalogue, from the fraction of galaxies with $z > z_{cluster}$ for each bin in magnitude, \textit{r'}, and color (\textit{g' - r'} and \textit{r' - i'}) - Figure\,\ref{weigh}. Hence, given the magnitude and the color of each galaxy, we assigned to it a weigh, \textit{w}, as the fraction of galaxies with $z > z_{cluster}$ in that bin. \\  \begin{figure} 

\caption{Fraction of galaxies with $z > 0.5$ ($n(z>0.5)/N_{tot}$), for different magnitudes in filter \textit{r'} and colors \textit{r'-i'}.}  \label{weigh}  \end{figure}  The average E-mode components correspond to the shear value which depends on the geometrical factor $ \beta = D_{LS}/ D_{L} $, where $D_{LS}$ is the angular diameter distance from the lens to the background source galaxy, and $D_{L}$ is the distance from the observer to the background galaxy. A galaxy at the same radial distance from the center of the cluster but at a different background redshift is sheared differently. To remove this variation, we divide the estimated shear by $\beta$, which results in the infinite redshift limit (z $\rightarrow \infty$) shear value, that is only function of the radial distance from the cluster center. To estimate $\beta$ we used once more Coupon's catalogue, since we can consider that this catalogue is complete up to our magnitude limit. We applied the photometric selection criteria to the catalogue and then we computed $\beta$ for the whole distribution of field galaxies, taking into account the contamination by foreground galaxies given our selection criteria by setting $\beta(z_{phot} < z_{cluster}) = 0$. The averaged geometrical factors for each cluster are given in Table\,\ref{table:2}.