I did a dry run of a presentation I'm giving and I noticed that when in full screen mode, the projector is cutting off a little bit of all four sides of the slide (appears to be overscan). I've tried getting the projector and laptop to correct for it but have been unsuccessful. As a hack, I'd like to just increase the distance between the header and footer and the edge of the slide. The style file I'm using contains

\ProvidesPackageRCS $Header: /cvsroot/latex-beamer/latex-beamer/themes/theme/compatibility/beamerthemeshadow.sty,v 1.12 2007/01/28 20:48:30 tantau Exp$

\mode<presentation>

\definecolor{BYUblue}{RGB}{0,31,69}
\definecolor{BYUgold}{RGB}{195,163,106}
\usecolortheme[RGB={0,31,69}]{structure} % BYU Blue

\usetheme{Frankfurt}
\setbeamercolor*{frametitle}{bg=BYUblue!50,fg=white!25}
\setbeamercovered{transparent}
\mode<all>

\begin{textblock*}{100mm}(0.95\textwidth,-0.7cm)
\includegraphics[width=1.2cm]{figures/magiccLabLogo}
\end{textblock*}}

% define the footline
\defbeamertemplate*{footline}{infolines theme}
{
\leavevmode%
\hbox{%
\hspace*{2mm}
\end{beamercolorbox}%
\hspace*{2mm}
\end{beamercolorbox}}%
\hspace*{2mm}
\end{beamercolorbox}%
\vskip0pt%
}

\setbeamertemplate{navigation symbols}{} % no nav symbols


I moved the footer up by increasing the dp setting of the beamercolorboxes to 2ex in the above footline definition above. Is there an easy way like that do that for the header?

This is what I have

This is what I want - just a little additional space just above the section titles

-
If you are able to provide a minimal working example (MWE) that the community can play with, it could be useful to diagnose the actual problem and how to fix it correctly. – Werner Jan 11 '14 at 5:24

So I've sort of figured it out. The Frankfurt theme uses the smoothbars outer theme. I navigated to the MiKTeX 2.9\tex\latex\beamer\base\themes\outer folder and made a backup copy of the beamerouterthemesmoothbars.sty file. I then edited it so the \AtBeginDocument command is now

\AtBeginDocument{
{
\colorlet{global.bg}{bg}
\usebeamercolor{frametitle}

\ifbeamer@sb@subsection
color(0ex)=(global.bg);%
}
color(0ex)=(frametitle.bg);%
color(1ex)=(frametitle.bg);%
}
\else
color(0ex)=(global.bg);%
color(8ex)=(section in head/foot.bg)% <- this was the only line I changed. It was 7ex.
}
color(0ex)=(frametitle.bg);%
color(1ex)=(frametitle.bg);%
}
\fi