Visualization of n-D Spectra

A 2-D spectrum is usually easier to read when displayed with one color (or one color for positive signals and another for negative signals). This clearly separates the spectrum from labels, integrals and other graphical elements. When several spectra are shown together through the overlay mechanism, each spectrum can have its own color.

Available Modes:

  1. Fast Plot: ideal during processing.
    • The same color palette is used for all spectra. You can select another palette in your user Settings or use the keyboard shortcuts 4 and 6 to cycle through all the available palettes.
  2. Contour Plot: ideal for printing, comparing two experiments or annotating. Four parameters regulate this mode:
    • Threshold: the intensity value of the first contour level. Signals of lower intensity are hidden.
    • Spacing: the constant ratio between the intensities of two adjacent levels.
    • The number of positive and the number of negative levels. The number of negative levels can be set to zero, in which case negative peaks are not displayed.
  3. Gradient Contour Plot: the lowest contour levels are faint and gradually become more prominent.
    • Use this stylish variation if you want to see very weak peaks without being distracted by them. It is slower than the standard contour plot.
  4. The Stacked Plot is particularly useful for arrayed spectra, for example an Inversion Recovery experiment. Each row is drawn as a standard 1-D spectrum.
    • Can be easily transformed into a skewed plot: drag the right margin toward the left.
  5. The Arrayed Plot is a variation of the above, useful for comparing relative signal intensities across the series.
    • The frequency scale still refers to the contour plot.
  6. Chessboard: each sub-plot is tagged with a numerical index.
    • This mode is suitable for visualizing small 3-D data sets.

To see the spectrum on a black background, press Shift-B: it swaps the colors of the background and the frequency scale.
The background and scales can be set to any color but only gray can be used for the optional grid.

Related Topics

Adding the Projections around a 2-D Plot

Changing the Font of the Frequency Scale

Web Tutorial

Create a Color Gradient