Vertical alignment of tabulars nested in longtable

Question

I tried to nest tabulars in a longtable enviroment. The content of the tabulars is still at the bottom of each row.

\begin{longtable}[c]{p{153mm-2\tabcolsep}p{37mm-2\tabcolsep}}\hline
   \begin{tabular}{p{44mm-2\tabcolsep}p{44mm-2\tabcolsep}p{29mm-2\tabcolsep}p{36mm-2\tabcolsep}}
    foo & bar & foofoo & barbar 
    \end{tabular}
    & \mynewline
    \hline
    \endhead
    %\setlength{\extrarowheight}{38mm}
    \begin{tabular}[t]{p{44mm-2\tabcolsep}p{44mm-2\tabcolsep}p{29mm-2\tabcolsep}p{36mm-2\tabcolsep}}
    Foo Bar & foo foo foo & \color{red} foo & bar \\
    \multicolumn{4}{l}{\textbf{Foo Bar}} \\
    \multicolumn{4}{l}{Bar: \textbf{Foo, Foo}} 
    \end{tabular}
    & \includegraphics[height=38mm,keepaspectratio]{image} \mynewline \hline
    \begin{tabular}[t]{p{44mm-2\tabcolsep}p{44mm-2\tabcolsep}p{29mm-2\tabcolsep}p{36mm-2\tabcolsep}} \\ \hline
    \end{longtable}

Answer 1

Your posted example doesn't run (private macros and more \begin than \end) If I fill out some missing pieces, it works as I expect with all the later entries aligning with the top row of the table in the first column.

\documentclass[a4paper,landscape]{article}
\usepackage{calc}
\usepackage{color,graphicx}
\usepackage{longtable}
%\pdfpagewidth=200mm
\def\mynewline{\\}
\def\includegraphics[#1]#2{picture here}

\begin{document}

\small

\begin{longtable}[c]{p{153mm-2\tabcolsep}p{37mm-2\tabcolsep}}\hline
   \begin{tabular}{p{44mm-2\tabcolsep}p{44mm-2\tabcolsep}p{29mm-2\tabcolsep}p{36mm-2\tabcolsep}}
    foo & bar & foofoo & barbar 
    \end{tabular}
    & \mynewline
    \hline
    \endhead
    %\setlength{\extrarowheight}{38mm}

    \begin{tabular}[t]{p{44mm-2\tabcolsep}p{44mm-2\tabcolsep}p{29mm-2\tabcolsep}p{36mm-2\tabcolsep}}
    Foo Bar & foo foo foo & \color{red} foo & bar \\
    \multicolumn{4}{l}{\textbf{Foo Bar}} \\
    \multicolumn{4}{l}{Bar: \textbf{Foo, Foo}} 
    \end{tabular}
    & \includegraphics[height=38mm,keepaspectratio]{image} \mynewline \hline
    \begin{tabular}[t]{p{44mm-2\tabcolsep}p{44mm-2\tabcolsep}p{29mm-2\tabcolsep}p{36mm-2\tabcolsep}} \end{tabular}\\ \hline



    \end{longtable}

\end{document}