ThermoFisher Scientific DXR xi, User Manual

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4
Troubleshooting
Problems and Solutions
Thermo Scientific DXRxi User Guide 173
• Make sure the sample is directly under the objective and in focus
• Make sure the shutter door on the grating is open
• The sample may not be Raman active; test the system by using a known good sample
If this problem persists, contact our sales or service representative in your area.
No Visible Image Appears in the Video Pane or Viewer
• If the illuminator is set to low intensity, set it to higher intensity
• Change the software to video mode
• Make sure the viewer selection control (below the video camera) is in the middle position
• Push the ND, FS and AS controls on the illuminator all the way in, if present
If this problem persists, contact our sales or service representative in your area.
The Spectrum Has a Sloping Background or a Severe Positive Offset
The sample may be heating. To account for this condition try one or more of the following:
• Use a different laser (shorter wavelengths heat samples less)
• If the sample looks burned, replace it or move it so the laser will strike a fresh area
• Reduce the laser power and collect the sample again
Watch the live display to see if the sample is still heating. (Reducing the laser power
reduces the Raman signal generated at the sample and therefore the quality of the data. To
compensate, try increasing the number of scans or the exposure time.)
• Reduce the exposure time and collect the sample again
• Turn on baseline correction in the settings panel
If this problem persists, contact our sales or service representative in your area.
The Spectrum Baseline Is Severely Tilted, Curved or Saturating
The sample is fluorescing during data collection. To correct this problem, try one or more of
the following:
• Turn on baseline correction in the settings panel
• Use a longer wavelength laser
• Go to live spectrum mode and expose the sample to the laser beam for a period of time
before beginning the collection of the sample spectrum.