Agilent Technologies 1220 Infinity II LC User Manual page 135

Table 23
Apex + Baselines
Apex + Slopes +
Baselines
All in Peak
Every 2nd spectrum
All
Range
Step
Threshold
1220 Infinity II LC System User Manual
Agilent 1220 Infinity II LC Diode Array Detector (DAD)
Spectrum Settings
Spectra are taken at the apex and baselines of the peak.
Spectra are taken at the apex, baselines, upslope, and downslope of the
peak.
All spectra within the peak are taken.
The three spectra acquisition types mentioned above are also referred
to as peak-controlled spectra acquisition. The peak detection is done by
the detector firmware based on the threshold and peakwidth
parameters you set for the DAD. If you want to use peak-controlled
spectra storage, make sure that you set these parameters to recognize
all the peaks of interest. The integration algorithm also includes peak
detection based on the threshold and peakwidth parameters set in the
integration events.
Spectra are taken continuously as for All, but only every second
spectrum is stored; other spectra are discarded. This reduces the
amount of data storage necessary.
Spectra are taken continuously depending on the setting of the
Peakwidth. Eight spectra are acquired per Peakwidth. The acquisition
time for one spectrum is slightly less than the Peakwidth divided by 8,
that is, greater than or equal to 0.01s and less than or equal to 2.55s.
If there are no peaks in Signal A, there are no spectra. You cannot
process spectra present in other signals.
Range defines the wavelength range for spectral storage.
Limits: 190 to 950 nm in steps of 1 nm for both low and high values. The
high value must be greater than the low value by at least 2 nm.
Step defines the wavelength resolution for spectral storage.
Limits: 0.10 to 100.00 nm in steps of 0.1 nm.
The threshold is the height in mAU of the smallest expected peak. The
peak detector ignores any peaks which are lower than the threshold
value and does not save spectra.
Limits: 0.001 to 1000.00 mAU in steps of 0.001 mAU. Usable for modes
Apex + Baselines, Apex + Slopes + Baselines and All in Peak
Detector Description
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