[Tex/LaTex] Beamer vs. TikZ: uncover nodes step-by-step

beameroverlaystikz-pgf

I'm trying to uncover a TikZ image piece-by-piece like so:

\documentclass{beamer}

\usepackage{tikz}
\usetikzlibrary{positioning} 

\begin{document}
\begin{frame}{Linearity}
\begin{center}
\begin{tikzpicture}
  \node (Ctx) {\visible<2->{$\Gamma$}};
  \node[below right=0.5cm and 0.1cm of Ctx] (E) {$E$};
  \node[below right=0.5cm and 0.1cm of E] (psi1) {\visible<3->{$\Psi_1$}};
\end{tikzpicture}
\end{center}
\end{frame}
\end{document}

However, this gives the following error message:

! Package tikz Error: Giving up on this path. Did you forget a semicolon?.

See the tikz package documentation for explanation.
Type  H <return>  for immediate help.
 ...                                              

l.16 \end{frame}

If I use \only instead of \visible, pdflatex runs OK but the output jumps around when going from slide to slide, since the invisible nodes don't take up space and thus the E node's position changes. So \visible is what I need.

Best Answer

In the one case I overlayed TikZ I was using \uncover<n-m>{ELEMENT} in order to show ELEMENT in slides n to m.