# Colored and opaque image background in Beamer with foilhead

My .tex is this

\documentclass[12pt,xcolor={usenames}]{beamer}
\setbeamercovered{transparent}
\setbeamertemplate{caption}[numbered]
\usepackage[spanish,es-tabla,es-nodecimaldot]{babel}
\usepackage[latin1]{inputenc}
\usepackage[T1]{fontenc}
\normalfont
\usepackage{beamerfoils}
\usepackage{tikz}
\usepackage{graphicx}
\usepackage{courier}
\usefonttheme{serif}

\definecolor{darkturquoise}{rgb}{0.0, 0.81, 0.82}

\beamertemplatetheoremsnumbered
\setbeamerfont{institute}{size=\small}
\title{{\bf\LARGE\color{white}Title Slide}\newline{\bf\color{white}Faculty}\newline{\bf\Large\color{white}Course}}
\author{\bf\color{white}Lecturer
\newline{\scriptsize\href{mailto:name@university.edu}{name@university.edu}}}
%\titlegraphic{\includegraphics[scale=0.3]{UW_logo}}
\date{}

\setbeamercovered{invisible}

\begin{document}

{\setbeamercolor{background canvas}{bg=darkturquoise}
\maketitle}

No color here

{\setbeamercolor{background canvas}{bg=darkturquoise}
Color here}

\begin{center}
{\Large opaque image here, bluish if possible}
\end{center}
\endfoil
\end{document}


I'm trying to give my third slide the same background color as the first one (darkturquoise), but I can't. Also, I'd like to put some image on my fourth slide as background (full slide). Also, is it possible to give it a bluish (darkturquoise) tint at the same time?

Maybe this image:

I have seen some solutions but they cannot be applied to the foilhead enviroment, I guess.

• Is there any reason why you need to use beamerfoils? Why don't you just use a regular frame such as {\setbeamercolor{background canvas}{bg=darkturquoise}\begin{frame}{Third slide} Color here \end{frame}}? Mar 17 at 6:48

Do you really need to use beamerfoils? Why don't you just use standard frames? Things are much better documented then:

\documentclass[12pt,xcolor={usenames}]{beamer}
\setbeamercovered{transparent}
\setbeamertemplate{caption}[numbered]
\usepackage{tikz}

\definecolor{darkturquoise}{rgb}{0.0, 0.81, 0.82}

\beamertemplatetheoremsnumbered
\setbeamerfont{institute}{size=\small}

\title{\texorpdfstring{
\textbf{\LARGE\color{white}Title Slide}\newline
\textbf{\color{white}Faculty}\newline
\textbf{\Large\color{white}Course}
}{Title Slide -- Faculty -- Course}
}
\author{\texorpdfstring{
\textbf{\color{white}Lecturer\newline
\scriptsize\href{mailto:name@university.edu}{name@university.edu}}
}{Lecturer: name@university.edu}
}
\date{}

\setbeamercovered{invisible}

\begin{document}

{\setbeamercolor{background canvas}{bg=darkturquoise}
\maketitle}

\begin{frame}{Second slide}
No color here
\end{frame}

{\setbeamercolor{background canvas}{bg=darkturquoise}
\begin{frame}{Third slide}
Color here
\end{frame}}

{\usebackgroundtemplate{
\begin{tikzpicture}[remember picture, overlay]
\node[at=(current page.center)] {
\includegraphics[keepaspectratio,
width=\paperwidth,
height=\paperheight]{example-image-a}
};
\fill[darkturquoise!25, blend mode=multiply] (current page.north east) rectangle (current page.south west);
\end{tikzpicture}
}
\begin{frame}{Fourth slide}
{\Large opaque image here, bluish if possible}
\end{frame}}

\end{document}


Some notes:

• Do not use \bf, this macro is deprecated. Use \textbf instead.
• It is probably a good idea to give an alternative PDF string for the title and author, so that it is printed in a reasonable way in the PDF's meta data.
• In general, you need to state the background color setting before starting the frame. So, you should create some scope using {}.
• Finally, you can place the image and overlay it with some tint using TikZ in combination with \usebackgroundtemplate as shown in the example above.

If you still want to stick with beamerfoils: Since setting the background color involves scoping, you need to end the relevant frame explicitly using \endfoil or using the \frame macro. Therefore, this should work:

{\setbeamercolor{background canvas}{bg=darkturquoise}
Color here
\endfoil
}


and also:

{\setbeamercolor{background canvas}{bg=darkturquoise}\frame{
Color here
}}


Similarly, you can do:

{\usebackgroundtemplate{
\begin{tikzpicture}[remember picture, overlay]
\node[at=(current page.center)] {
\includegraphics[keepaspectratio,
width=\paperwidth,
height=\paperheight]{example-image-a}
};
\fill[darkturquoise!25, blend mode=multiply] (current page.north east) rectangle (current page.south west);
\end{tikzpicture}
}