Leica DM1000 LED manual Trouble shooting Problem Cause/Remedy, Focus

11. Trouble shooting

Problem Cause/Remedy

Fluorescence: The lamp does not illuminate immediately upon being switched on.

￿The external power supply must be switched on repeatedly

￿Hot Hg lamps should cool down before switching on again

Focus

The specimen cannot be brought into focus.

Darkfield

￿Use the correct immersion medium

￿Lay the specimen with the cover glass to- wards the top

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

No definite DF contrast is possible.	￿Be sure that a DF objective is being used
	￿The objective aperture setting is too high
	(maximum 0.75/1.10); if necessary, reduce the
	objective aperture using the iris diaphragm on
	the objective
	￿Check the condenser centering
	￿Open the aperture diaphragm completely

The image is unevenly or not uniformly illuminated.

￿The magnification is too weak. Use a higher magnification

Undesirable stray light.	￿Clean the specimen and neighboring lenses
	(→ p. 54)
Polarization

No polarization contrast is possible.

￿Bring the polarizer and analyzer into cross po- sition until they reach maximum darkness (without specimen) (→ p. 45)

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