[Tex/LaTex] Vertical alignment of blocks with and without columns

Question

In a beamer presentation, when I work with blocks in columns, LaTeX seems to add some additional vertical space before the title of the first block. How can I avoid this behaviour?

A minimal working example:

\documentclass[t]{beamer}

\begin{document}

\begin{frame}{Frame without columns}
  \begin{block}{Just a block}
  \end{block}
\end{frame}

\begin{frame}{Frame with columns}
  \begin{columns}[t, onlytextwidth]
    \begin{column}{0.45\textwidth}
      \begin{block}{A block in a columns area}
      \end{block}
    \end{column}
  \end{columns}
\end{frame}

\end{document}

Answer 1

Beamer add this space for non-text elements (blocks, itemize, ...) at the top of columns. To undo this, you can add a negative space:

\documentclass[t]{beamer}
\usecolortheme{orchid}

\begin{document}

\begin{frame}{Frame without columns}
  \begin{block}{Just a block}
  x
  \end{block}
\end{frame}

\begin{frame}{Frame with columns}
  \begin{columns}[t, onlytextwidth]
    \begin{column}{0.45\textwidth}
        \vspace*{-\baselineskip}
      \begin{block}{A block in a columns area}
      x
      \end{block}
    \end{column}
  \end{columns}
\end{frame}

\end{document}