- 15 -
Height (H) = (1 + (Bottom - Top)) x the Calibration Factor (µm per pixel)
Width (W) = (1 + (Right - Left)) x the Calibration Factor (µm per pixel)
Depth (D) = User defined value determined by the dimensions of the flow cell used during the analysis
Note: The Calibration Factor (used for H and W) is factory determined and the value set as a default
value.
The Volume per Picture is calculated as D × H × W (µm
3
)
VisualSpreadsheet can determine the total volume it imaged with the following calculation:
Total Volume Imaged = Number of Images Taken during the Run × Volume per Picture (µm
3
)
VisualSpreadsheet can calculate PPM using either the ESD or ABD measurements.
Total Volume of Particles using ESD or ABD (µm
3
)
PPM = ————————————————————— X 10
6
Total Volume Imaged (µm
3
)
Particle Count 1 x 10
12
(µm
3
)
P/mL = ———————————— X ———————
Total Volume Imaged (µm
3
) 1 (mL)
To locate the values used in the above calculations, from the Main window:
·
For Height and Width, Setup > Context > Capture (tab) > Acceptable Region (section), to view
the total number of pixels from left to right, and from top to bottom.
·
For Depth, Setup > Context > Flow Cell (tab) > Flow cell (section) for the “Flow cell depth”
value (populated from the Flow Cell Database file).
·
For total number of camera images, Setup > Context > Run Summary (tab) > Images > Total.
Setup and Focus (Camera Image Preview)
The Setup and Focus window (Setup Menu or Hotkey = F6) is used to adjust the focus, camera, and
context settings of the FlowCAM while sample is present in a flowcell. By default, in AutoImage
Mode, the camera images the field of view at a regular interval-determined by the AutoImage Rate
setting in frames per second (Setup > Context > Camera > Timing [section]). The resulting images are
displayed in the Setup and Focus window. This window can be used for centering the flow cell, or for
“real time” particle monitoring. Note that Raw camera images shown in the Setup and Focus window
are neither captured nor saved with the following exception: before exiting Setup & Focus mode or
while paused, the last image in the viewer can be saved (this is described in more detail in Section Four).
