Optika Italy B-510 Series, Instruction Manual

Page: 19 / 162

Page 19
30-20%
10.8.3 Aperture diaphragm (AS)
1. Move the selector
①
on the reflected light illuminator in the
position corresponding to letter “R”
(only B-510MET-R)
. (Fig.
23)
2. Completely pull out the aperture diaphragm selector
④
to
fully close the diaphragm. (Fig. 26)
3. Remove one eyepiece.
4. While looking into the empty eyepiece sleeve, use the
provided Allen wrench into the centering screws
⑤
to bring
the bright spot in the center of the field of view. (Fig. 26)
5. The illuminator is centered when the diaphragm image is
symmetrical to the field of view.
• The Numerical Aperture (N.A.) value of the aperture
diaphragm affects the image contrast. Increasing or reducing
this value one can vary resolution, contrast and depth of
focus of the image.
• With low contrast specimens move the diaphragm lever to
about 70%-80% of the objective’s N.A. If necessary, remove
on eyepiece and, looking into empty sleeve, adjust the
condenser’s ring in order to obtain an image like the one in
Fig. 27.
F Fig. 26 ig. 26
F Fig. 27 ig. 27
④
⑤
FIELD OF VIEW
APERTURE
DIAPHRAGM
70-80%
F Fig. 28 ig. 28
②
③
①
④
10.9 Centering the condenser (B-510MET-R)
1. Place the specimen on the stage, insert 10x objective into
the light path and focus.
2. Insert the front lens of the swing-out condenser
①
. (Fig. 28)
3. Rotate the field diaphragm ring
②
in counterclockwise
direction, to fully close the diaphragm.
4. Rotate the condenser height adjustment knob
③
to focus the
edges of the diaphragm.
5. Rotate the two centering screws
④
to bring the bright spot in
the center of the field of view.
6. Gradually open the diaphragm. The condenser is centered
when the diaphragm image is symmetrical to the field of view.
7. In normal use, open the diaphragm until it circumscribes the
field of view.
F Fig. 29 ig. 29
①
10.10 Aperture diaphragm
• The Numerical Aperture (N.A.) value of the aperture
diaphragm affects the image contrast. Increasing or reducing
this value one can vary resolution, contrast and depth of
focus of the image.
• With low contrast specimens set the numerical aperture value
①
(printed on the condenser ring) to about 70%-80% of the
objective’s N.A. (Fig. 29) If necessary, remove on eyepiece
and, looking into empty sleeve, adjust the condenser’s ring in
order to obtain an image like the one in fig. 27.
Example: with objective PLAN 40x / 0,65 set the scale to 0.65
x 0.8 = 0,52