particularly in the central field of view at low magnifications. In such a case, use Low Mag mode for observation at low magnifications.
Turning Specimen Bias Voltage ON and OFF may cause change of focus, astigmatism and aperture alignment and need adjustment.
Astigmatism correction range is enlarged when the box is checked. Use it for observation of ferromagnetic specimens such as iron that make astigmatism correction difficult.
The Degauss operation eliminates hysteresis of the magnetic field in the objective lens.
When focus is changed greatly, accuracy of magnification or alignment of the electron optical axis may degrade due to hysteresis of the focusing magnetic field. Click Degauss button under the following conditions:
After changing focus widely.
Before making the electron optical axis alignment.
Degaussing is automatically effected when WD is changed in the Column Condition raea, when the accelerating voltage is changed, or when a new Probe Current mode is selected.
(2) LOW MAG MODE block
Probe Current mode and Cond Lens1 are set as same manner as in the HIGH MAG MODE area.
These are selectable independently to High mag mode because in general the Low mag mode brings less bright image if operated with the same column condition.
(3) ABCC Link
When the ABCC Link check box has been checked, ABCC will start automatically when some of the column conditions are changed. Image brightness will be adjusted to adequate value.
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