# Trying to insert a background image via TikZ results in extra white-space around the corners

I am trying to insert a background image in my beamer template as follows:

\documentclass[10pt,c,aspectratio=169,a4paper]{beamer}
\usepackage{tikz}

\setbeamertemplate{background}{
\begin{tikzpicture}%
\node {\includegraphics[width=\paperwidth,height=\paperheight,keepaspectratio]{example-image-a}};
\end{tikzpicture}
}

\begin{document}

\section{Introduction}

\begin{frame}

\end{frame}
\end{document}


this results in

as you can see, due to some sort of bounding box around the inserted image, there is a space from the north-west corner of the image in (x-y). However, I would like to position the image in the starting at the north-west corner.

You need to set inner sep=0pt.

\documentclass[10pt,c,aspectratio=169,a4paper]{beamer}
\usepackage{tikz}

\setbeamertemplate{background}{
\begin{tikzpicture}%
\node[inner sep=0pt] {\includegraphics[width=\paperwidth,height=\paperheight,keepaspectratio]{example-image-a}};
\end{tikzpicture}
}

\begin{document}

\section{Introduction}

\begin{frame}

\end{frame}
\end{document}


• thanks a lot for the hint ;). – Raaja Apr 1 at 13:52