Some buttons and menu options are not functional yet, as this is a work in progress.

To open a file:

  1. Click on the folder icon on top left corner or select File -> Open from menu.
  2. Select the desired file and data type in the file dialog and click “Open”.
  3. The file will be listed in the “Data List” window (top half of left panel).
  4. To remove the file from “Data”, click on “trash can” icon at lower right corner of the “Data List” window.

To plot the spectrum that is now loaded, click on the plot icon (lower left corner of the Data window). It will be plotted in the central window. Basic statistics for the displayed spectrum will be shown in the “Statistics” window at the lower left.

Each spectrum loaded will have its own layer, as shown the “Layer List” window at the lower left. New layers are created each time a spectrum is modified or a fit is performed, and the original spectrum is untouched. To work on the file of interest, click on its plot window to bring it in focus.

To adjust plot display:

  1. If your mouse has center wheel, it can be used to zoom in and out while the cursor is over the plot.
  2. Click on the “big wheel” icon on top of the plot to change top axis parameters or displayed units.
  3. Left click on the plot to bring up a context menu.
  4. Select “View All” to view all available data (if zoomed in).
  5. Select “X Axis” or “Y Axis” to adjust respective axis behaviors.
  6. Select “Mouse Mode” to toggle between 3-button and 1-button mouse.
  7. More plot options are available under “Plot Options”.
  8. Select “Export…” to save plot out as an image.

To select a region of interest (ROI):

  1. Select the layer from “Layers” list (if you have multiple).
  2. Click on the “rectangle” icon on the top left of the plot. An adjustable rectangle will appear on plot display.
  3. Click and drag the edges to adjust wavelength coverage. As the region changes, basic statistics in the “Statistics” window on bottom left of the viewer will also update accordingly.
  4. Click inside the rectangle and drag to reposition it without resizing.
  5. Click the left-most “knife” button under “Layers” (bottom left of the left panel) to create a new layer slice from the ROI.
  6. To remove a layer slice, select the layer and click on “trash can” button under “Layers”.
  7. To remove ROI, left click while it is highlighted and select “Remove ROI” from the context menu.


Layer arithmetic (the “calculator” button under “Layers”) is work in progress.

To measure equivalent width and related properties:

  1. Select the layer from “Layers” list (if you have multiple).
  2. Add three ROIs.
  3. Position the orange ROI over the emission or absorption line of interest and adjust accordingly.
  4. Position each of the blue ROIs over two different continuum areas, one on each side of the emission/absorption line.
  5. As you adjust the regions, values for equivalent width etc. will be updated under the “Measured” tab under “Statistics” on top right of the viewer.


When multiple ROIs are present, the statistics in “Basic” tab reflect all data points contained in the ROIs.

To fit a model to the selected ROI, see Model Fitting.

To quit SpecViz, select File -> Exit from menu.