Adjusting the Lighting
Specimens of different size, thickness, and color variations will require different levels of illumination. There are two ways
to change the amount of illumination when viewing a specimen; adjusting the Abbe condenser and adjusting the iris
diaphragm (see Figure 3f):
1. When viewing with lower power (4x and 10x) objective lenses you will need to lower the condenser lens in order to
spread the light over the larger field of view. To change the position of the condenser, simply rotate the condenser
regulator knob clockwise until the beam of light spreads wide enough to illuminate the entire field of view when
viewing.
2. As you lower the condenser to spread out the light or change to a higher power objective lens, your image will appear
dimmer. Open the aperture of the iris diaphragm to let in more light. Opening and closing the diaphragm will give
a relief view of the specimen and allow you to change the depth of field of the specimen being viewed.
Using a Filter
To bring out different levels of detail, experiment with changing the color of the back lighting of the specimen. To change
the lighting color, place the blue filter in the light path by placing it on the top of the electric illuminator. You may need to
refocus by adjusting the fine focus knob (11) slightly for best viewing.
Replacing the Electric Illuminator Bulb
To replace a burned out bulb, do the following:
12
ee
1. Take out the thumbscrew on the
illuminator by turning it counter
clockwise.
2. Open the compartment and you will s
the 20 watt tungsten bulb.
3. Remove the bulb by pressing lightly
down on the bulb and rotate it counter
clockwise and it will come out.
4. Take the new bulb and line up the pins
of the bulb with the slots in the bulb
socket and then push it down and rotate
clockwise until it sets in place.
5. Close the compartment, line up the
.threaded hole for the thumbscrew and
Figure 3g tighten it by turning clockwise.
Thumbscrew