Leica DMI6000B, DMI3000B, DMI4000B manual Operation Dark Field TL

8. Operation

8.2.3 Dark Field (TL)

Note:

The maximum usable objective aperture for dark field is for the condenser S1 0.70 and for the condenser S23/S28 0.40.

Leica DMI3000 B:

¥Select a dark field objective.

¥Select the suitable dark field stop on the con- denser.

¥Open the aperture of the condenser com- pletely.

¥Remove all other optical components such as analyzers, polarizers or IC prisms from the beam path.

¥Insert a dark field specimen.

¥Set the brightness at the light potentiometer

¥Focus the image with the focus wheels.

Leica DMI4000 B and Leica DMI6000 B:

¥Use the TL/IL function button to switch to transmitted light (TL).

¥Select the DF (dark field) contrast method by pressing the variable button BF. Alternatively: press the variable button

CHANGE TL .

(For details on button assignments, please see the identification sheet.)

DF will appear on the LeicaScreen. Motorized condensers will now switch to the dark field ring. Coded condensers must be switched manually.

¥Insert a transmitted light specimen.

¥Rotate an appropriate objective into place.

¥Focus the image with the knob on the SmartMove or the focusing wheel and adjust the intensity with the INT function buttons.

When selecting the dark field method, the aper- ture diaphragm is opened fully and can not be adjusted.

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