Bresser National Geographic 40X-640X Instrucciones De Uso página 12

Now you can observe in the same way as described in the previous section.
TIP: The higher the magnification you use the more light is required for a good illumination of the pic-
ture. Therefore, always start your experiments with a low magnification.
5. Condition and prepare viewed objects
5.1. Condition
With the Barlow lens nearly fully extended, your microscope's magnification can be doubled. Both
transparent and non-transparent specimens can be examined with this microscope, which features
both direct and transmitted light. If opaque specimens are being examined, such as small animals, plant
parts, tissues, stones and the like, the light is reflected from the specimen, through the lens and eye-
piece, where it is magnified, to the eye (reflected light principle, switch position I). If opaque specimens
are being examined, the light from below goes through the specimen, lens and eyepiece to the eye and
is magnified en route (direct light principle, switch position II).
Some small water organisms, plant parts and animal components are transparent by nature, but many
others require pretreatment — that is, you need to make a thinnest possible slice of the object by hand
cutting or using a microtome, and then examine this sample.
5.2. Creation of thin preparation cuts
Specimens should be sliced as thin as possible. A little wax or paraffin is needed to achieve the best
results. Put the wax into a heat-safe bowl and heat it over a flame until the wax is melted. You can use
a candle flame to melt the wax.
DANGER!
Be exremely carfeful when dealing with hot wax, as there is a danger of being burned.
Then, dip the specimen several times in the liquid wax. Allow the wax that encases the specimen to
harden. Use a MicroCut or other small knife or scalpel to make very thin slices of the object in its wax
casing.
DANGER!
Be extremely careful when using the MicroCut, knife or scalpel. These instruments are
very sharp and pose a risk of injury.
Place the slices on a glass slide and cover them with another slide before attempting to view them with
the microscope.
5.3. Creation of your own preparation
Put the object to be observed on a glass slide and cover the object with a drop of distilled water using
the pipette (12).
Set a cover glass (available at a well-stocked hobby shop) perpendicular to the edge of the water drop,
so that the water runs along the edge of the cover glass. Now lower now the cover glass slowly over
the water drop.
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