One side of the image is out of focus. The nosepiece is not in the
II. Mechanical Section:
The coarse focus knob is hard to
turn.
The focus is unstable.
III. Electric section
The LED doesn't turn on.
The brightness is not enough
The light blinks
IV. Viewing tube assembly
The field of view of the two eyes is
different
V. Microphotography and video
The image is unfocused
The edge of the image is unfocussed To some degree, it is inherent
Bright patches appear on the image
center of the light path
The specimen is out of place
(tilted)
The optical performance of the
sample cover glass is poor
The tension adjustment collar is
too tight
The tension adjustment collar is
too loose
No power supply
The brightness adjustment is
low
The power cord is poorly con-
nected
The interpupillar distance is not
correct
The dioptric correction is not
right
The viewing technique is not
correct, and the operator is
straining the eyesight
Incorrect focussing
to the nature of achromatic
objectives
Stray light is entering the
microscope through the eye-
pieces and through the camera
viewfinder
Page 19
Turn the nosepiece to a click stop
Place the specimen flat on the stage.
Use a cover glass of better quality
Loosen the tension adjustment collar
Tighten the tension adjustment collar
Check the power cord connection
Adjust the brightness
Check the power cord
Adjust the interpupillar distance
Adjust the dioptric correction
When look into the objective, do not stare
at the specimen but look at the whole field
of view. Periodically, move the eyes away
to look at a distant object, then back into
the objective
Adjusting the focus system as in the pres-
ent manual
The problem can be minimized by a correct
setting of the aperture diaphragm
Cover the eyepieces and the viewfinder
with a dark cloth