Subfig reference index off, but only when caption is above figure

Question

I want to reference a subfigure, but I found the index referencing is one off if the caption is above the big figure. MWE:

\documentclass[12pt,a4paper]{scrartcl}

\usepackage{subfig}
\usepackage{hyperref}
\usepackage{cleveref}

\begin{document}

\begin{figure}%
    \centering
    \caption{Example of powerset transformation}%
    \label{fig:powerset_ex}
    \subfloat[NFA] {
        \label{subfig:powerset_nfa}
        Some NFA%
    }
    ~ $\rightarrow$ ~
    \subfloat[DFA] {
        \label{subfig:powerset_dfa}
        Some DFA%
    }
\end{figure}

In \Cref{fig:powerset_ex} we turn the NFA \Cref{subfig:powerset_nfa} into the DFA \Cref{subfig:powerset_dfa}

\end{document}

This results in the output:

In Figure 1 we turn the NFA Figure 2a into the DFA 2b.

when it should read 1a and 1b, respectively. I found that the labels are referenced correctly if I move the caption and label of the whole figure below both subfigures. But I want the figure caption above. How can I achieve this?

Answer 1

At first I thought this was peculiar to figures, but it also affects tables. I guess it is a subfig bug which was preserved in subcaption.

One solution is to play with the figure counter, but I prefer to use saveboxes.

BTW, there is no align option for \includegraphics. Instead one can use \raisebox, but subfig and subcaption require different solutions.

\documentclass[12pt,a4paper]{scrartcl}
\usepackage{graphicx}
\usepackage{subcaption}
\usepackage{hyperref}
\usepackage{cleveref}

\begin{document}

\begin{figure}%
    \sbox0{\subfloat[DFA\label{subfig:powerset_nfa}] {%
        \includegraphics[width=0.4\textwidth]{example-image-a}%
    }}%
    \sbox1{\subfloat[NFA] {% works either way
        \label{subfig:powerset_dfa}
        \includegraphics[width=0.4\textwidth]{example-image-b}%
    }}%
    \centering
    \captionsetup[figure]{position=top}%
    \caption{Example of powerset transformation}%
    \label{fig:powerset_ex}
    \raisebox{-0.5\height}{\usebox0}
    ~ $\rightarrow$ ~
    \raisebox{-0.5\height}{\usebox1}
\end{figure}

In \Cref{fig:powerset_ex} we turn the NFA \Cref{subfig:powerset_nfa} into the DFA \Cref{subfig:powerset_dfa}

\end{document}