+\subsection{Convert - Interpolate to Parallel}
+This command filters divergent projection data (equiangular or
+equilinear) and interpolates (or rebins) to estimate the projection
+data if the projections had been collected with parallel geometry.
+
+\subsection{Analyze - Plot Histogram}
+Plots a histogram of projection data attenuations.
+
+\subsection{Analyze - Plot T-Theta Sampling}
+Plots a 2-dimensional scattergram showing the \texttt{T} and
+\texttt{Theta} values for each data point in the projection data.
+This is especially instructive when scanning with divergent
+geometries and the scan ratio is close to \texttt{1}.
+
+\subsubsection{Theta Range}\label{IDH_DLG_THETA_RANGE}
+This dialog box allows the constraint of Theta values for the
+T-Theta Sampling scattergram.
+