Bresser NATIONAL GEOGRAPHIC 40X-640X Instrucciones De Uso página 12

3. Normal observation
For normal observation, place the microscope in a bright location (near a window or desk lamp, for exam-
ple).
Turn the focus knob (2) to the upper stop, and set the objective turret (3) to the lowest magnification.
Now, turn on the light using the switch on the microscope base. You'll find further tips about the light
source in the next section. Now, place a prepared slide (10) under the clips on the stage (4), directly under
the objective (1). When you take a look through the eyepiece, you can see the magnified specimen. At this
point, you still might see a slightly fuzzy picture. Adjust the image sharpness by slowly turning the focus
knob (2). You can now select a higher magnification by turning the objective turret and selecting a different
objective.
When you do so, note that the sharpness of the picture must be adjusted again for the higher magnifica-
tion. Also, the higher the magnification, the more light you will need for good illumination of the picture.
The wheel with pinhole apertures (16) below the microscope stage (4) will help you in viewing very bright
or clear-sighted preparations. Turn the wheel (16) till the best contrast is achieved.
4. Observation (electronic light source)
For observation with the electronic light source (6) you need to insert 2 AA batteries 1.5 V, in the battery
compartment (8) on the base of the microscope (7). The battery compartment is opened using a Phillips
screwdriver. Insert the batteries with the correct polarity (+/- indication). Put the battery cover first into
the small opening so that the lid fits perfectly. Now you can tighten the screw. The lighting is switched on
when you turn the switch on the microscope base. Now you can observe in the same way as described in
the previous section.
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