\begin{tikzpicture}
	\begin{axis}[%
		xmin=-25, xmax=25,
		ymin=-2500, ymax=2500]
		\addplot graphics [xmin=-25, xmax=25, ymin=-2500, ymax=2500] {example-grid-100x100bp.png};
	\end{axis}
\end{tikzpicture}%