Two images aligned to the center of the page in first slide in Beamer

Here's a beamer solution for \maketitle. It puts both logos into \titlegraphic, aligned at the middle. I used an asterisk for the date to verify the center adjustment.

\documentclass[demo]{beamer}
\usetheme{Copenhagen}
\title{Presentation Title}
\author{Author}
\date{*}
\titlegraphic{%
  \mbox{}%
  \llap{\includegraphics[width=2cm]{logo1}\quad}%
  \rlap{\quad\includegraphics[width=4cm]{logo2}}}
\begin{document}
\maketitle
\end{document}

• \llap and \rlap hide the real width of the images.
• \raisebox{-\height}{...} shifts their baseline to the top for top alignment.