# Problems with \usebackgroundtemplate

When I use a figure in \usebackgroundtemplate I nothe that the figure in the background does not adjust in my presentation. See the figure below:

The shadows become white and the figure as background is shifted to the right. In addition, I would like to eliminate the primary pallete (which is in blue).

I would like the whole image to be in the background, without the white parts.

Below, my code:

\documentclass[xcolor=table,10pt,c]{beamer}
\usetheme{Warsaw}
\useoutertheme{infolines}
\usepackage[utf8]{inputenc}
\usepackage[portuguese]{babel}
\usepackage{tikz,pgfplots}
\usepackage{xcolor}
\usepackage{pgfpages}
\usepackage{graphicx,color}

%Dados da sua apresentação
\author[Aliano, A. F \& Fulano, G. H]{Angelo Aliano Filho \\ Fulano de Tal}
\title[Título resumido]{Título completo}
%\setbeamercovered{highly dynamic}
\setbeamercovered{transparent=30}
\institute[Seu inst.]{\textbf{Universidade Tecnológica Federal do Paraná} \\ Departamento de Matemática}
\date{\today}
\logo{
\includegraphics[scale=0.08]{logoUTFPR.png}
}

\usebackgroundtemplate{
\tikz\node[opacity=0.7] {
\includegraphics[width=\paperwidth,
height=\paperheight]
{lousa.jpg}
};}

\begin{document}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{frame}
\titlepage
\end{frame}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{frame}{Frame 1}{Subtitle 1}
Contents
\end{frame}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{frame}{Frame 1}{Subtitle 1}
\begin{block}{Title}
Content of a block...
\end{block}
\end{frame}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\end{document}

• How does it look when you deactivate \usetheme{Warsaw}? If your background image is shifted to the right, it is also shifted downwards, according to the lines appearing. Could you provide for lousa.jpg? And have a look in the documentation whether there is a default offset - either in usebackgroundtemplate or in beamer in general. – C. Peters Jul 22 at 6:47
• The lousa.jpg can be found in this adress: google.com/… – Angelo Aliano Filho Jul 22 at 13:52