+\begin{description}
+ \item[Smooth:] serves to make the graph more homogeneous, improving its visualization.
+ \item[Refresh on Stop ON:] [checked -- only for Transport buttons] scopes are updated when you stop playback at a given location. Instead, they are locked at the start position while you playback. This saves system resources and makes playback smoother. By dragging the cursor the scopes are updated in realtime.
+ \item[Refresh on Stop OFF:] [unchecked -- for Transport buttons and dragging cursor] the display of the scopes is synchronized with the playback. Every variation of the graphs is in realtime. There may be some decrease in fps during playback.
+ \item[Refresh on Release:] This works for the Viewer and Compositor windows. Scopes are not updated during playback. The update occurs only when you stop playback, that is at the final position (either by dragging the cursor or using the Transport buttons). When in the timeline, if you drag on the TimeBar or reposition in the TimeBar in either Drag and Drop or Cut and Paste mode, the release of the button also will update the Scopes. This saves system resources and makes playback smoother. Because there is no update when playing in the main window, you can still easily get a videoscope update simply by moving the mouse to the Compositor and a single click there will update the scopes without changing the frame (as long as Click to Play is not enabled).
+\end{description}
+
+ The lower section, called \textit{VectorWheel Grids}, it is only active when VectorWheel is set up in Scopes pull-down and contains four entries (figure~\ref{fig:videoscope06}):
+
+ \begin{figure}[hbtp]
+ \centering
+ \includegraphics[width=1.0\linewidth]{videoscope06.png}
+ \caption{Pull-down Settings}
+ \label{fig:videoscope06}
+ \end{figure}
+
+ \begin{description}
+ \item[None:] It only shows the colour wheel, without any superimposed graticula.
+ \item[All:] Shows the most complete grid that allows precise and useful measurements. It also shows the skintones area.
+ \item[Hue:] Show a more minimal grid. It also shows the I-Line.
+ \item[IQ:] Show shows only I-Line and Q-Line.
+ \end{description}
+
+
+You can create custom grids. These are raster .png images of adequate resolution and must be put in:
+
+\begin{lstlisting}[style=sh]
+[your cinelerra path]/bin/plugins/scopes/custom_grid.png
+\end{lstlisting}
+
+More information in the later section on Vectorscope.
+
+\paragraph*{Sliders:} allow for varying the \textit{solidity} of the dots shown in Waveforms and Vectorscope. You can get to the subpixel level for precision. They are accompanied by Reset buttons that restore them to default values.
+
+
+
+\subsubsection*{Waveform/RGB Parade/Waveform Ply}%
+\label{ssub:waveform_rgb_parade_ply}
+
+The \textit{Waveform Scope} displays image intensity (luminance) versus image $X$ position. The \textit{Waveform RGB} displays image RGB intensity versus image $X$ position (one graph per channel). The \textit{Waveform Ply} shows the three channels in a single graph. The Waveform Scope appears on the left side or in the middle of the Videoscope window. The display is calibrated vertically from $0\%$ intensity (black) at the bottom up to $100\%$ intensity (white) at the top. Each column of pixels in the image corresponds to one column of pixels in the Waveform Scope (figure~\ref{fig:videoscope02}). Note that the height of the values of a waveform/waveform RGB corresponds exactly to the values on the $x\, axis$ in the \textit{histogram}. A vertical/horizontal correspondence is therefore obtained.