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b.
Autocorrelation
is an indicator of resolution. The mass at the center of the
window will become sharper with smaller particles and better focus.
c.
Mean
shows the data that is being subtracted as part of the Background (based
upon the
Background %
described above). Showing the Mean can be helpful for
highlighting stuck particles and other anomalies in the flow.
d.
RMS
is an indicator of the amount of useful signal available for the calculations.
e.
Show Text
turns on and off the text-based velocity display.
f.
Show Vector
displays an arrow in the direction of the flow. The size of the arrow
will change with velocity. You can also set the
Scale
to increase or decrease the
arrow size.
6.2
Polygon and Macropixel intensity probes
Intensity or polygon probes are used to track the color spectrum or fluorescence intensity
inside a defined region. The advantages of the polygon probe are that (1) you can make the
probe an arbitrary shape to fit your region of interest, and (2) for color images, the probe can
independently track the intensity of the red, blue, and green signals. The macropixel probe is
limited to a rectangular shape; however, it can be broken into multi-pixel arrays to obtain
spatially resolved intensity data. The macropixel probe also allows time averaging of probe
output data.
6.2.1
Polygon intensity probes
To create a probe:
1.
Click the
Intensity Probe
toolbar button
to highlight the button.
2.
With your mouse curser over the image, right click on the mouse and select New Probe.
Click on the image to draw the outline of the probe. When the shape is defined double
click the mouse to close the polygon. A probe such as the one below will appear.
