Calibration Window

This window displays the measured and expected peak positions while calibrating an overlay. See Calibrating Spectra for how to use this. The combination box on top selects the overlay that is being worked on.

The grid contains the following items:

Measured	The peak position, normally entered by click and drag on the experimental spectrum
Actual	The true peak position, typically entered by click and drag on the calibration spectrum after pressing the assign button
Residual	Observed-Calculated from last fit
Weight	Weight of the point in the fit; the number is proportional to the estimated standard deviation, so use larger numbers for less accurate measurements. A negative or zero weight is used to flag a point to be excluded from the fit.

	Select the spectrum to calibrate
	Assign current peak; the "Actual" cell of the current row will turn red, and will be filled in by the position of the next peak you measure.
	Fit to given order of polynominal
	Undo last fit
	Copy selected lines to clipboard
	Delete selected lines
	Open custom fit dialog - allows the use of any function, not just a polynomial
	Delete unassigned lines
	Other operations - shows an additional menu, described below.
	Select order of polynomial for calibration fit
	Displays root mean square error of current fit

Other... Operations

Copy Frequency To...	Copy Frequency scale to another overlay; this process assumes that the two overlays have exactly the same x axis (i.e. the ith point on each overlay corresponds to the same frequency). Any x axis on the target overlay is thus discarded. (Contrast with "Apply Calibration To" below.) This is intended for use on spectra recorded simultaneously.
Apply Calibration To...	Apply calibration curve to other overlay. This applies the calibration function of the current overlay to the x axis of the target overlay, so there is no requirement for the frequency scales to match. (c.f. "Copy Freqeuency to" above.) This is intended to transfer a calibration curve of, for example, voltage to frequency, from one spectrum to another.
Clear	Delete all lines
Set Range	Set approximate range
Reset	Reset calibration to default, i.e. FrequencyScale=1, FrequencyOffset=0
Etalon	Given two approximately spaced peaks, find all the others