# caption not centered for subfigure

I have three plots which I want to display one after the other. It displays fine but the only problem I have is the captions are not centered. the subcaptions are more obvious after rendering the picture below.

\documentclass{article}

\usepackage[utf8]{inputenc}
\usepackage{graphicx}
\usepackage{subcaption}

\begin{document}
\begin{figure*}

\hspace*{-1.1in}
\begin{subfigure}[b]{\textwidth}
\centering
\includegraphics[scale=0.37]{dummy.jpg}
\caption{\small a image }
\label{fig:subfigure1}
\end{subfigure}
\vskip\baselineskip
\hspace*{-1.1in}
\begin{subfigure}[b]{\textwidth}
\centering
\includegraphics[scale=0.37]{dummy.jpg}
\caption[]%
{{\small b image}}
\label{fig:subfigure2}
\end{subfigure}
\vskip\baselineskip
\hspace*{-1.1in}
\begin{subfigure}[b]{\textwidth}
\centering
\includegraphics[scale=0.37]{dummy.jpg}
\caption[]%
{{\small c image}}
\label{fig:subfigure3}
\end{subfigure}

\caption[ whole image caption here]
{\small whole image caption here}
\label{fig:experiments}
\end{figure*}

\end{document}

I am adding the image because it is extra wide, it is what I am using as a test

https://i.stack.imgur.com/5wjJ6.jpg

• You probably want something like width=\linewidth rather than scale. If you want to increase the text block width temporarily, use something like changepage. And then look at the configuration options for configuring sub-captions and captions e.g. font size, alignment etc. – cfr Jun 19 '18 at 1:39

As @cfr has already pointed out in a comment, you should replace the three [scale=0.37] options with [width=\textwidth]. Omit the three redundant \centering instructions and replace both instances of \vskip\baselineskip\hspace*{-1.1in} with \vspace{1\baselineskip}. Finally, run the instruction \captionsetup{font=small} to save yourself from having to insert \small in the body of each and every \caption instruction.

\documentclass[demo]{article} % omit 'demo' option in real document

\usepackage[utf8]{inputenc}
\usepackage{graphicx}
\usepackage{subcaption}

\begin{document}
\begin{figure*}
\captionsetup{font=small} % font size for caption and subcaptions
\begin{subfigure}[b]{\textwidth}
\includegraphics[width=\textwidth]{dummy.jpg}
\caption{a image }
\label{fig:subfigure1}
\end{subfigure}

\medskip
\begin{subfigure}[b]{\textwidth}
\includegraphics[width=\textwidth]{dummy.jpg}
\caption{b image}
\label{fig:subfigure2}
\end{subfigure}

\medskip
\begin{subfigure}[b]{\textwidth}
\includegraphics[width=\textwidth]{dummy.jpg}
\caption{c image}
\label{fig:subfigure3}
\end{subfigure}

\caption[whole image caption here]{whole image caption here}
\label{fig:experiments}
\end{figure*}

\end{document}
• thank you for the answer. The plots are nicely arranged and with centered captions now but I would like to be able to stretch the image so as to spill in the margins on both sides. Making it larger than width=\textwidth and start it from somewhere in the left margin space . This is why I thought \hspace*{-1.1in} would work, but seems to be dragging the captions with it. – zaranaid Jun 19 '18 at 19:09