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11. Troubleshooting
Review the information in the table below to troubleshoot operating problems.
PROBLEM
CAUSE
SOLUTION
I. Optical Section:
The illumination is on, but the field of
view is dark.
The plug of the power supply is
not connected to the illumina
-
tion set
Connect them
The brightness is too low
Adjust to a proper setting
Too many colour filters have
been stacked
Minimize the number of the filters
The edge of the field of view is
vignetted or the brightness is asym
-
metric.
The nosepiece is not in the cor-
rect position
Turn the nosepiece to a click stop
The color filter is partially
inserted
Insert the filter to full depth
When using 4x objective the
diffusion lens is not inserted
Insert the lens
The phase contrast slider is not
in the proper position
Move the slider to a click stop
Dust and stains can be seen in the
field of view.
There are stains and dust on
the specimen
Clean the specimen
There are stains and dust on
the eyepiece
Clean the eyepiece
There is an apparent double image.
The size of the aperture dia
-
phragm is too small
Open the aperture diaphragm
T
he condenser is not properly
centered or it is at a wrong
height
Set the condenser according to Koehler
settings.
Poor image quality:
The image is not sharp
The contrast is not high
The details are not clear
The phase contrast is low.
The nosepiece is not in the
center of the light path
Turn the nosepiece to a click stop
The aperture diaphragm in
the view of field is opened too
much or too little
Adjust the aperture diaphragm
The lenses (condenser, objec
-
tive, eyepieces are culture
dish) is dirty
Thoroughly clean all the optical system
In phase contrast observation,
the bottom thickness of the
sample is more than 1.2mm
Use a sample holder whose bottom
thickness is less than 1.2mm
A bright field objective is used
for phase contrast observation
Switch to a phase contrast objective
The condenser ring is not
aligned with the objective
phase ring
Adjust the condenser ring to match the
objective phase ring
The light ring and/or the phase
contrast ring is not centered
Adjust the bolts to center them
The objective used is not com
-
patible with the phase ring
Please use a compatible objective
The phase contrast depends on
the sample position
The sample holder is not flat. Move the
sample around until a compatible area is
found.
