After using the condenser vertical motion lever to move the condenser to its upper limit, slightly lower the condenser, so the tip does not protrude from the top of the stage.
If the diffuse surface of the illumination optics appears as a rough background when the specimen is in focus, move the condenser up and down so that the rough background is not visible.
Align the aperture diaphragm lever
Align the condenser aperture diaphragm lever to the same value as the magnifying power of the objective. By doing this, the aperture diaphragm will be throttled to 70 to 80% of the objective's numerical aperture, allowing sufficient
contrast.
