# Caption package not working with beamer

I am using beamer to make a presentation. But the default caption font size seems big to me. So I tried to make the font size smaller using caption package. I tried this:

\usepackage[center,scriptsize]{caption}


Also:

\usepackage{caption}
\captionsetup[figure]{font={footnotesize},labelfont={footnotesize}}


But they don't seem to make the caption font size smaller. Where am I going wrong?

My preamble is:

\documentclass{beamer}
\usepackage{mathtools}
\usepackage{graphicx}
\usepackage{lmodern}% http://ctan.org/pkg/lm
\graphicspath{{images/}}
\usetheme{default}


And my caption code is:

\begin{figure}[h]
\centering
\includegraphics[scale=0.8]{axb-grid}
\caption{$A \times B$ grid}
\label{fig:axbgrid}
\end{figure}


You don't need the caption package for this.

Simply issue the command

\setbeamerfont{caption}{size=\footnotesize}


MWE

\PassOptionsToPackage{demo}{graphicx} % remove in your document
\documentclass{beamer}
\usepackage{mathtools}
\usepackage{graphicx}
\usepackage{lmodern}% http://ctan.org/pkg/lm
\graphicspath{{images/}}
\usetheme{default}

\setbeamerfont{caption}{size=\footnotesize}

\begin{document}
\begin{frame}
\begin{figure}[h]
\centering
\includegraphics[scale=0.8]{axb-grid}
\caption{$A \times B$ grid}
\label{fig:axbgrid}
\end{figure}
\end{frame}
\end{document}


Output:

## EDIT

While with old versions of beamer, caption commands used to work, it seems that now the caption package is not able to recognize beamer anymore.

In fact, loading caption with beamer you get the following warning:

Package caption Warning: \caption will not be redefined since it's already

(caption) redefined by a document class or package which is

(caption) unknown to the caption package.

See the caption package documentation for explanation.

If you want caption and its \captionsetup to work with beamer, you have to load caption with the option compatibility=false:

\usepackage[compatibility=false]{caption}


but, as the documentation warns:

But please note that using this option is neither recommended nor supported since unwanted side-effects or even errors could occur afterwards.

• Thanx, this works like a charm. But I still would like to know why caption package is not working. Hence, I can't accept your answer. – th1rdey3 Jan 24 '14 at 9:25
• @th1rdey3 do you think that now it can be accepted? – karlkoeller Jan 24 '14 at 10:02
• There was a typo in the beamer code, which needed fixing for other reasons. Regrettably, caption checks for this defective definition before coming into action: a fix is needed in caption. – Joseph Wright Jan 24 '14 at 10:09
• @JosephWright thanks for this clarification. – karlkoeller Jan 24 '14 at 10:11
• Interesting, I am using miktex with gvim tex-plugin. This warning didn't show up when I compiled. – th1rdey3 Jan 24 '14 at 10:35

These Issues have been cleared and should be closed in 2019 versions of the packages

Please update to Tex Live 2019 (Note W32TeX / MiKTeX are generally already updated)