Leica DMI6000B, DMI3000B Troubleshooting Problem Cause/Remedy Bright field, Dark Field, → p, 103

9. Troubleshooting

Problem Cause/Remedy

Bright field

The specimen can not be brought into focus.

￿Use the correct immersion medium.

￿Place the specimen on the stage with the cov- erslip facing down.

￿Make sure that the cover glass thickness is correct and that it suits the indication on the objective.

￿Ensure that you are using an objective with coverslip correction.

￿Adjust the correction ring on the objective if present.

Dark Field

No definite DF contrast is possible.

￿Be sure that a DF objective is being used. ￿The objective aperture is too high:

maximum 0.7 for condenser S1 maximum 0.4 for condenser S23/28

If necessary, reduce the objective aperture using the iris diaphragm on the objective.

￿Check the condenser centering.

The image is unevenly or not uniformly illumi- nated.

￿The magnification is too weak. Use a higher magnification.

￿Remove the condenser head or condenser lenses.

Undesirable stray light.	￿Clean the specimen and neighboring lenses
	(→ p. 107).

103