Applied Biosystems Data Explorer 4 Series User Manual page 212

Chapter 5 Examining Spectrum Data
Manually
calibrating a
single spectrum
5
5-8 Applied Biosystems
NOTE: Multi-point calibration yields higher mass accuracy
than one-point calibration. Selecting calibrant peaks that
bracket the mass of interest also yields higher mass
accuracy.
To manually calibrate a single spectrum:
1. Click the Spectrum window to activate it, then select
the spectrum trace of interest.
2. From the Peaks menu, select Peak Label, set the Mass
Label Type to Centroid, then click OK.
NOTE: For spectra containing broad peaks that have
unresolved adducts or impurities such as proteins, you
may obtain better results if you use apex instead of
centroid settings.
3. From the Process menu, select Mass Calibration, then
select Manual Calibration.
The Manual Mass Calibration dialog box is displayed
(Figure 5-2).