Viewing a Specimen
Your instrument is provided with a mechanical stage with a stage holder clamp and directional knobs –see figure 4g and 4h.
A vernier scale on both axes allows the exact marking and replication of an object in the field of view that the user may
want to come back to.
1. Use the clamp lever to open the clamping arm of the stage holder clamp.
2. Place a specimen slide (3” size) inside the holder and gently close the clamping arm against the slide.
3. Use the stage movement knobs (see Figure 4h) to position the specimen over the opening in the stage (5).
You are now ready to focus and view the specimen, but first you must take some precautions so as not to damage the
specimen slide or objective lens. Your microscope is equipped with a safety rack stop (9) which allows you to regulate the
range of travel on the focuser. This assures that the objective lens will not accidentally come into contact with the
specimen slide, breaking the slide or scratching the objective lens. To adjust the travel on the focus mechanism:
4. Raise the objective lens away from the specimen stage (5) by rotating the coarse focus knob (3) backwards
(clockwise).
5. Unthread the safety rack stop screw (9) about 2/3 of the way.
6. Turn the nosepiece (12) until the 40x lens is over the specimen.
7. Lower the objective lens over the slide until the tip of the lens is slightly above the specimen slide. (Be careful not to
touch the objective lens to the slide).
8. Thread the safety screw (9) upward until it stops against the focus mechanism.
9. Rotate the knurled locking nut upward to lock the safety screw in place.
Iris Diaphragm
Abbe Condenser
Stage
Movement Knobs
Figure 4g Figure 4h
Tip: To position the specimen directly under the objective lens, close the opening on the iris diaphragm (see Figure 4h)
until it is almost completely closed. You should see a small beam of light projected onto the specimen slide. Now simply
use the stage movement knobs to move the specimen directly inside the beam of light.
10. Use the nosepiece (12) to rotate the objective lenses (4) until the 4x objective is directly over the specimen. Always
start with the lowest power objective and work your way up to higher powers.
11. Look through the eyepiece while turning the coarse focus knob (3) until the specimen comes into view. You may
need to adjust the stage knobs (Figure 4h) slightly to center the specimen in the field of view. Warning: When
focusing, be careful not to raise the specimen stage so high that the specimen slide touches the objective lens.
Not only can you break your slide but you may scratch the objective lens.
12. Finally, adjust the fine focus knob (11) until you reach the sharpest focus for your eye. Warning: Never rotate
both of the fine focus knobs at the same time in opposite directions or the focusing mechanism may get
damaged.
Tip: When viewing a specimen with the 100x objective lens, you can improve the resolving power by placing a small drop
of immersion oil between the specimen and objective lens. For specimen slides that you prepare yourself, always cover the
specimen with a thin piece of glass and place the oil on the cover glass. Do not put the oil directly on the specimen sample.
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