http://www.guit.sssup.it/phpbb/viewtopic.php?p=55902
Questo dovrebbe fare al caso tuo, permette di “sforare” nel margine esterno
Fran
emc:`\documentclass{book}
\usepackage[demo]{graphicx}
\usepackage{ifthen}
\makeatletter
\newcounter{largefigure}
\newenvironment{largefigure}[1][htp]
{\begin{figure}[#1]
\refstepcounter{largefigure}\label{lf@\thelargefigure}
\ifthenelse{\isodd{\pageref{lf@\thelargefigure}}}
{\def\largefigureside{l}}{\def\largefigureside{r}}}
{\end{figure}}
\newcommand{\largeincludegraphics}[2][]{%
\makebox[\columnwidth][\largefigureside]{\includegraphics[#1]{#2}}}
\makeatother
\usepackage{lipsum}
\begin{document}
\lipsum[1]
\begin{largefigure}[t]
\largeincludegraphics[width=1.2\textwidth]{qqq}
\caption{La mia didascalia}\label{fig:prova1}
\end{largefigure}
\lipsum[2-5]
\begin{largefigure}[t]
\largeincludegraphics[width=1.2\textwidth]{qqq}
\caption{La mia didascalia}\label{fig:prova2}
\end{largefigure}
\end{document}`