User Manual
16
150
Series
T
roubleshooting
Common Issues 
Symptom
Cause
Remedy
OPTICAL ISSUES
One side of the field
of view is darker
The nosepiece if misaligned  Turn the nosepiece until it clicks into place 
Stains or dust has accumulated on the objective,
eyepieces, or base lens 
Clean all lenses with lens cleaner or a lint free non-
abrasive cloth 
Obstructions  are
observed in the field
of view
Stains, dust, or dirt has accumulated on the speci-
men 
Clean the slide or use a new specimen if sample is
destroyed 
Stains, dust, or dirt have accumulated on the lens  Clean the lens 
Unclear Image
There is no cover slip on the slide  Add a cover slip. The objectives are designed for use
with a 0.17mm cover slip, so it is a requirement to
use one for proper images. 
The cover slip is not standard sized  Replace the cover slip with the appropriate 0.17mm 
thickness slip 
The aperture is not open to an appropriate diam-
eter 
Adjust the aperture to have the light just larger than
the size of the condenser 
Stain or dust has accumulated on the lens in the
inlet of the head 
Clean  the lens with lens cleaner or a  nonabrasive
lint free cloth, as well as spray with compressed air 
One side of the field
of view is dark or the
image moves while
focusing
The specimen slide is not fixed  Secure the slide to the stage with clips 
The nosepiece is not in the right position  Turn the nosepiece until it clicks into place 
The field of view is not
bright enough
The iris disc diaphragm is not big enough  Rotate the iris disc diaphragm to allow  more light
to travel 
Stains, dust, or dirt has accumulated on the con-
denser, objective, eyepieces, or base lens 
Thoroughly clean tall lenses with lens cleaner or a
lint free nonabrasive cloth 










