Leica DM2700 M, Инструкция по эксплуатации

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11. Trouble Shooting
Problem
The illumination “fl ickers.”
Fluorescence: The lamp does not illuminate im-
mediately upon being switched on.
Brightfi eld
The specimen can not be brought into focus.
Darkfi eld
No defi nite DF contrast is possible.
The image is unevenly or not uniformly illumi-
nated.
Cause/Remedy
Be sure that there is no loose connection at the
power supply.
If present, replace the old lamp (lamp housing
107/2 or 106z) (
→
p. 26ff).
The external power supply must be switched
on repeatedly.
Hot Hg lamps should cool down before switch-
ing on again.
Use the correct immersion medium.
Lay the specimen with the cover glass toward
the top.
Make sure that the cover glass thickness is
correct and that it suits the indication on the
objective.
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 magnifi cation is too weak.
Use a higher magnifi cation.
Open and center the fi eld diaphragm and,
where applicable, the aperture diaphragm.