Spectra Settings Area

This whole GUI area is disabled if an image is displayed rather than a spectrum.

Show I/I_0

If this box is unchecked, the raw spectrum is plotted. If this box is checked, the spectrum is normalized to a reference spectrum (see below how to set the reference). In this case, $-\log I/I_0$ is plotted.

Set to I_0

Click this button to set the currently displayed spectrum as reference spectrum. If you subsequently open spectra and check the Show I/I_0 box, they will be normalized to this reference spectrum.

Current I_0 file

will display the file name of the spectrum which is currently set as reference spectrum.

Note the following:

• The eV range for the reference spectrum must be greater than or equal to the eV range of the displayed spectrum if you want to show $I/I_0$ (this applies to the upper and the lower end of the eV range).

• If you display $I/I_0$, make sure you display the same signal type and detector / display (see below) as when you set $I_0$. Otherwise, your spectrum won't make any sense. This is especially important for the silicon detector, where a lot of different signals can be displayed. Of course only the bright field signal (sum of all segments) makes real sense for spectra, but make sure that you don't set a different one by accident (neither when setting $I_0$ nor when displaying a normalized spectrum).