Molecular Devices QPix 420, User Manual

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QPix 420 Colony Picking System User Guide
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To adjust the test image:
1. From the Receptacle list, select the number of the receptacle to view and click the frame to
view in the receptacle image below the list. The frame is in red.
2. Under Acquisition, adjust the Exposure and Gain settings.
In the Exposure (ms) field, enter the number of milliseconds (from 1 to 2000) to expose
the sample to light when acquiring the image.
Adjust the Gain to increase the image signal without changing the light exposure.
Tip: You should not change the default Gain setting for Blue-White colony detection.
After you adjust the Exposure or Gain settings, click Grab Image to apply the settings to the
test image.
3. Select the Detection tab.
4. In the Threshold intensity histogram, click and drag the red slider line to the right of the
large spike to view the White colonies as green spots. Click and drag the red slider to the
left of the large spike to view the Blue colonies as dark black spots against the background.
The X-axis represents the intensity and the Y-axis represents the relative area at that
intensity. Selecting blue or white colonies requires setting an Intensity Range.
In the Intensity Range table, select the Low and High Threshold values.
To select the Low intensity value, move the red slider line left to the lowest value, and
Ctrl+Click. The value displays in the table cell.
To select the High intensity value, move the red slider line right to the highest value,
and Ctrl+Click. The value displays in the table cell.