Locate the Beam

1. Locate a hole in the sample at any magnification in the normal magnification mode (between 2k – 200k).
2. Illuminate the center 2 – 10 cm of the TEM screen.
3. Clear the beam path to the filter (retract unused detectors and raise the viewing screen).
4. Select EELS mode in the Microscope System palette.
5. Finally, click on the Center ZLP button in the Microscope System palette to align the beam.

Note: The ZLP is very intense and can easily saturate the detector. For systems with a fast electrostatic shutter, it is a simple matter of enabling Auto exposure mode or manually changing to a shorter exposure time to prevent saturation. On other systems, you may need to reduce the beam current. In TEM image mode, you can easily adjust the condenser, but in scanning (S)TEM or diffraction mode, it is not as simple. Changing the spot size or emitter properties may be necessary.

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