Nexcope NIB620 - Page 64

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100%
CT
F
Illustration 55 F: NIB630 - Adjustment of aperture diaphragm.
Aperture diaphragm
(condenser diaphragm)
Aperture diaphragm lever (1) to the right:
The aperture diaphragm is closed 
reducing resolution and brightness, and
increasing contrast and depth of field.
Aperture diaphragm lever (1) to the left:
The aperture diaphragm is open, which
increases resolution and brightness and
reduces contrast and depth of field.
Adjusting the aperture diaphragm
Check that the 10x objective is
placed in the beam path.
Close the aperture diaphragm  aperture
diaphragm lever (1) to the right.
Loosen the small screw on the eyepiece
sleeve to remove one of the eyepieces (2).
Use a suitable hexagonal screwdriver
Insert the centering telescope (CT) (3) in the
eyepiece sleeve. Rotate the CT to adjust
the focus. This reveals the objective pupil
plane (4) and the image of the aperture
diaphragm (5).
Move the aperture diaphragm lever (1) to
the left so that the size of the diaphragm
image (5) is 70-80% of the size of the
objective pupil plane (4). This setting gives a
reasonable contrast and a favourable image.
After adjustment, remove the CT and reinsert
the eyepiece. Tighten the set screw again.
For further explanations,
see chapter 4.4.3.
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G
Illustration 55 G: NIB630 - Sample observation.
Sample observation
Rotate the brightness control knob (1) to
adjust the brightness of the field of view.
Rotate the fine focusing knob (2) to focus on
the sample.
When replacing and observing the
sample always check the brightness
and the focus - adjust them as necessary.
For further explanations, see
chapter 4.3.2. and 4.3.5.
NIB630
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