[Tex/LaTex] Reduce section, subsection font size in beamer sidebar

beamerfontsize

I have the same problem listed here:

Reduce fontsize beamer sidebar

Except the given answer there does not work. Thanks to the rules here at Stack Exchange, I am not allowed to post any comments asking the person who posted the answer there to clarify their example.

I am using the following settings in my beamer:

\usetheme[left]{Marburg} 
\setbeamerfont{section in sidebar}{size=\fontsize{2}{4}\selectfont}
\setbeamerfont{subsection in sidebar}{size=\fontsize{2}{4}\selectfont}
\setbeamerfont{section in sidebar shaded}{size=\fontsize{2}{2}\selectfont}

With the intention being to reduce the font size of the sections and subsections listed in the sidebar. However, these commands do not do anything. Is there an explanation or example of how they are supposed to be used in order to adjust the font size?

This also has no effect:

\setbeamerfont{section in sidebar}{size=\tiny}

maybe the default font size is already tiny?

edit: Minimum working example

\documentclass[8pt]{beamer}
\usetheme[left]{Marburg} %  width=
\setbeamerfont{section in sidebar}{size=\fontsize{2}{4}\selectfont}
\setbeamerfont{subsection in sidebar}{size=\fontsize{2}{4}\selectfont}
\setbeamerfont{section in sidebar shaded}{size=\fontsize{2}{2}\selectfont}
\begin{document}

\section{Section 1}
\subsection{Subsection 1}
\begin{frame}{}
test
\end{frame}

\end{document}

Best Answer

Font size

TeX is quite obstinate regarding font size. It suggests you to apply the font size that is available, and would not like to rescale its fonts.

If you do want to rescale fonts like what we did in MS word, we could use the fonts that we used in MS word. In some sense, those fonts are designed to be rescaled.

% !TEX program = XeLaTeX

\documentclass[8pt]{beamer}
\usetheme[left]{Marburg} %  width=
\setbeamerfont{section in sidebar}{size=\fontsize{2}{4}\selectfont}
\setbeamerfont{subsection in sidebar}{size=\fontsize{2}{4}\selectfont}
\setbeamerfont{section in sidebar shaded}{size=\fontsize{2}{2}\selectfont}

\usepackage{fontspec}
\setmainfont{Arial Unicode MS}\setsansfont{Arial Unicode MS}

\begin{document}

\section{Section 1}
\subsection{Subsection 1}
\begin{frame}{}
test
\end{frame}

\end{document}

Showing only current section's subsections

There is a BEAMER option called hideothersubsections that hids other section's subsection.

\documentclass[8pt,hideothersubsections]{beamer}
\usetheme[left]{Marburg}

\begin{document}

\section{Section 1}
\subsection{Subsection 1-1}
    \begin{frame}
        test \\[6cm]
        test
    \end{frame}

\subsection{Subsection 1-2}
    \frame{}
\subsection{Subsection 1-3}
    \frame{}

\section{Section 2}
\subsection{Subsection 2-1}
    \frame{}
\subsection{Subsection 2-2}
    \frame{}
\subsection{Subsection 2-3}
    \frame{}
\section{Section 3}
\subsection{Subsection 3-1}
    \frame{}
\subsection{Subsection 3-2}
    \frame{}
\subsection{Subsection 3-3}
    \frame{}

\end{document}
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