# removing subfigure captions without removing labels

I tried using subfigure along with a caption for these four images according to the code shown below.

\begin{figure}[H]
%\centering
\begin{subfigure}[t]{0.49\textwidth}
%\centering
\includegraphics[width=\linewidth]{g1_2}
\caption{\SI{10}{\nano\meter}$\times$\SI{10}{\nano\meter} raw image of the surface of epitaxial graphene, $\left(U_T=+\SI{100}{\milli\volt}, I_T=\SI{500}{\pico\ampere}\right)$, $z=0\to\SI{34.768}{\pico\meter}$}
\label{figp1a}
\end{subfigure}%
\hfill
\begin{subfigure}[t]{0.49\textwidth}
%\centering
\includegraphics[width=\linewidth]{g2_2}
\caption{\SI{10}{\nano\meter}$\times$\SI{10}{\nano\meter} raw image of the surface of epitaxial graphene, $\left(U_T=+\SI{100}{\milli\volt}, I_T=\SI{500}{\pico\ampere}\right)$, $z=0\to\SI{45.534}{\pico\meter}$}
\label{figp1b}
\end{subfigure}

\begin{subfigure}[t]{0.49\textwidth}
%\centering
\includegraphics[width=\linewidth]{g_bilayer_2}
\caption{\SI{6.5}{\nano\meter}$\times$\SI{6.5}{\nano\meter} raw image of the surface of epitaxial graphene, $\left(U_T=+\SI{100}{\milli\volt}, I_T=\SI{500}{\pico\ampere}\right)$, $z=0\to\SI{47.548}{\pico\meter}$}
\label{figp1c}
\end{subfigure}%
\hfill
\begin{subfigure}[t]{0.49\textwidth}
%\centering
\includegraphics[width=\linewidth]{g_bilayer_zoom_2}
\caption{\SI{2.3}{\nano\meter}$\times$\SI{2.3}{\nano\meter} zoomed in section from fig.\ref{figp1c}, $\left(U_T=+\SI{100}{\milli\volt}, I_T=\SI{500}{\pico\ampere}\right)$}
\label{figp1d}
\end{subfigure}

\caption{STM imaging of different areas of the epitaxial graphene sample, prior to the deposition.}\label{figp1}
\end{figure}


The image result is as follows.

I would like to obtain the boundary of the resulting cross as a new path, which one can draw or fill.

So, I tried to remove the captions and try again with this code

\begin{figure}[H]
%\centering
\begin{subfigure}[t]{0.49\textwidth}
%\centering
\includegraphics[width=\linewidth]{g1_2}
%\caption{\SI{10}{\nano\meter}$\times$\SI{10}{\nano\meter} raw image of the surface of epitaxial graphene, $\left(U_T=+\SI{100}{\milli\volt}, I_T=\SI{500}{\pico\ampere}\right)$, $z=0\to\SI{34.768}{\pico\meter}$}
\label{figp1a}
\end{subfigure}%
\hfill
\begin{subfigure}[t]{0.49\textwidth}
%\centering
\includegraphics[width=\linewidth]{g2_2}
%\caption{\SI{10}{\nano\meter}$\times$\SI{10}{\nano\meter} raw image of the surface of epitaxial graphene, $\left(U_T=+\SI{100}{\milli\volt}, I_T=\SI{500}{\pico\ampere}\right)$, $z=0\to\SI{45.534}{\pico\meter}$}
\label{figp1b}
\end{subfigure}

\begin{subfigure}[t]{0.49\textwidth}
%\centering
\includegraphics[width=\linewidth]{g_bilayer_2}
%\caption{\SI{6.5}{\nano\meter}$\times$\SI{6.5}{\nano\meter} raw image of the surface of epitaxial graphene, $\left(U_T=+\SI{100}{\milli\volt}, I_T=\SI{500}{\pico\ampere}\right)$, $z=0\to\SI{47.548}{\pico\meter}$}
\label{figp1c}
\end{subfigure}%
\hfill
\begin{subfigure}[t]{0.49\textwidth}
%\centering
\includegraphics[width=\linewidth]{g_bilayer_zoom_2}
%\caption{\SI{2.3}{\nano\meter}$\times$\SI{2.3}{\nano\meter} zoomed in section from fig.\ref{figp1c}, $\left(U_T=+\SI{100}{\milli\volt}, I_T=\SI{500}{\pico\ampere}\right)$}
\label{figp1d}
\end{subfigure}

\caption{STM imaging of different areas of the epitaxial graphene sample, prior to the deposition.}\label{figp1}
\end{figure}


Now the image result is as follows

This image concept is Ok with me, but unfortunately, the labels for the four images namely \label{figp1a}, \label{figp1b}, \label{figp1c} and \label{figp1d} do not seem to work any more, because I commented the captions within the subfigures. I need the second image with the labels working.

• Do you want to print only (a) but not the text? If you remove everything, how to refer to 3.1(a) if it does not exist? – Sigur Jan 2 '18 at 19:32
• Please do not post fragments only – user31729 Jan 2 '18 at 19:37
• No, but I should be able to refer to the image itself as 3.1(a), but I will put (a), (b), (c), (d) on the image corners within the image area not separately. – ubuntu_noob Jan 2 '18 at 19:38
• @ChristianHupfer: What do you mean? – ubuntu_noob Jan 2 '18 at 19:40
• @ubuntu_noob: You're posting non-compilable fragments of code. There's no \documentclass etc. here, no list of used packages, no \begin{document}...\end{document} and the images are unavailable to us as well – user31729 Jan 2 '18 at 19:41

To make @Mico happy. The subcaption package has a command for this, namely \phantomsubcaption.

\documentclass{article}
\usepackage{todonotes}
\usepackage{subcaption}
\begin{document}
\begin{figure}
\begin{subfigure}[t]{0.49\textwidth}
\missingfigure[figwidth=\linewidth]{marmots are cute}
\phantomsubcaption
\label{figp1a}
\end{subfigure}%
\hfill
\begin{subfigure}[t]{0.49\textwidth}
\missingfigure[figwidth=\linewidth]{koala bears are also cute}
\phantomsubcaption
\label{figp1b}
\end{subfigure}

\begin{subfigure}[t]{0.49\textwidth}
\missingfigure[figwidth=\linewidth]{but in this forum, people love ducks}
\phantomsubcaption
\label{figp1c}
\end{subfigure}%
\hfill
\begin{subfigure}[t]{0.49\textwidth}
\missingfigure[figwidth=\linewidth]{I dunno why}
\phantomsubcaption
\label{figp1d}
\end{subfigure}
\caption{Marmots, koala bears and ducks.}
\end{figure}
The most important message is the one of Figure~\ref{figp1a}. But you may also
like the one of Figure~\ref{figp1b}. Figure~\ref{figp1d} contains a question.
\end{document}