Technical data

Data Acquisition 4
Estimate of worklist file size
Agilent 6200 Series TOF and 6500 Series Q-TOF LC/MS System Concepts Guide 115
much data when operated in the 2 GHz mode (extended
dynamic range or extended mass range) or 4 times as much data
when operated in the 4 GHz mode (high resolution).
Method parameters that control file size
LC data is usually a small fraction of TOF or Q-TOF data. The
size of the acquired data file depends on these TOF or Q-TOF
method parameters:
• Data file storage type—Profile, Centroid, Both or None
Profile stores raw data as abundance values for evenly spaced
ion flight time. Centroid stores only the assigned peaks but not
the raw data. Both stores both Profile data and Centroid
data. None stores no data but does store spectrum metadata
and method parameters.
If you want to analyze your data in Qualitative Analysis using
either the Large Molecular Feature Extractor (LMFE)
algorithm or the Deconvolute (MS): Maximum Entropy
algorithm, you acquire in either Profile or Both modes.
Profile data is required for both of these algorithms.
• Total run time
• Setting of time segments
• Number of experiments that are defined
Approximate file size for stored Profile data
The file size per spectrum depends on three variables.
• Mass range
• Spectrum metadata
• Compression factor - the data file is compressed by a factor
of 2 to 20, depending on the complexity of the mass spectra
acquired
Mass range You can reduce data file size by reducing the mass
range of interest. Profile data are stored as abundance for each
flight time. If you restrict the mass range, the number of data
points in the spectrum depends on the mass calibration curve.
The table below shows the number of possible data points for a