Blocks inside columns and progressive uncover

[Olaf Marzocchi]

Hello,
in the research center where I work someone built a beamer template
coherent with the official colors and style, and I am using it. In
this template blocks have the corners correctly rounded, so I use them
as containers for graphics, as frames in other words where the title
of the block contains a short caption.
This however causes some problems, especially with the progressive
uncovering of such blocks when placed inside columns environments.
I explain.

If I have an empty slide just with blocks and graphics, everything is
ok: the first slide is empty (in this example), the second one shows
the first block correctly (solid color), the third one the first one
and the second blocks.

\frame{
\frametitle{Title}
\begin{visibleenv}<2->
\begin{block}{Caption1}
\centering
\includegraphics{image1}<2->
\end{block}
\end{visibleenv}
\begin{visibleenv}<3->
\begin{block}{Caption1}
\centering
\includegraphics{image2}<3->
\end{block}
\end{visibleenv}
}

If I put it inside a columns environment, where the first column has
itemize and the second one has the graphics, the display of the blocks
doesn't work correctly anymore: the blocks and the contained images
are placed correctly (nothing, one, both, both) but the blocks are
painted translucent until the last step of the slide (nothing,
translucent one, translucent both, solid both):

\frame{
\frametitle{Title}
\begin{columns}

\begin{column}{0.5\textwidth}
\begin{itemize}
\item text1
\pause
\item text2
\pause
\item text3
\pause
\item text4
\end{itemize}
\end{column}

\begin{column}{0.5\textwidth}
\begin{visibleenv}<2->
\begin{block}{Caption1}
\centering
\includegraphics{image1}<2->
\end{block}
\end{visibleenv}
\begin{visibleenv}<3->
\begin{block}{Caption1}
\centering
\includegraphics{image2}<3->
\end{block}
\end{visibleenv}
\end{column}

\end{columns}
}

Could someone help me finding the problem or suggest a different
solution?

Thank you very much.

Bye,
Olaf

[Olaf Marzocchi]

As additional detail, I am using

\setbeamercovered{transparent}

in the header of the tex file.

Olaf

[Olaf Marzocchi]

The problem does not depend on the columns, the presence of an itemize
environment in the slide is already enough to show the problem: I
tested by enclosing the blocks in textblocks (package textpos) and by
having an itemize environment without columns. The blocks inside the
textblocks are fine.

Help? Ideas? am I doing something basically wrong and it is my fault?

Thank you
Olaf