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these values. Therefore the measure values will not be captured unless a trigger event occurs on a
separate channel, which was selected for triggering. Finally the channels are monitored in series, not
parallel, and it recommended to trigger on either fluorescent channels or scatter.
Threshold:
The value needed by a fluorescence or scatter measurement to cause the FlowCAM to take
a raw image. The threshold value should be set above the background noise level which is usually
around 150-200. The factory default value for Threshold is 400 and should not be changed by the user.
Scatter Detector
The Scatter Detector consists of an array of detectors. These detectors are numbered and correspond to
the numbers displayed in this section. For each magnification, the optimal Scatter Detectors have been
factory determined and preset in this section. Typically, the FlowCAM user should not adjust these
settings.
Laser
Enable Laser:
The laser (while on) can be disabled by unchecking this box. This is useful when
changing out objectives, etc. Please refer to the FlowCAM Safety section at the beginning of this
manual for a listing of precautions regarding laser safety.
Fluorescence Scale
Linear or Log:
The user can choose to report the peak and area values of the fluorescence and scatter
signals in either a linear or logarithmic scale. Reporting these values occurs at the time of acquisition
and cannot be changed after the analysis has finished. Standard output is typically linear scale.
Ignore raw images with more than one particle:
This option is useful when accurate fluorescent
measurements are important.
If you select this option, the software will discard raw images that contain
more than one particle. Raw images that contain more than one particle may have false fluorescent or
false light scatter data. It is important to note that when this option is selected, the count data will not be
accurate. These inaccurate counts are due to discarded particles that do not add to the particles per ml
count or the PPM calculation. If accurate count data is required, it is recommended that you dilute your
sample to produce a Particles Per Used Image value of 1.00-1.10 and complete your data capture with
this option disabled. See Section Two for more information on Trigger Mode and Particles Per Used
Image.
Advanced PMT Settings
