Bresser Junior 8855001 Mode D'emploi page 13

Now place the prepared
Fig. 3
specimen
19) directly
the objective on the
microscope stage (Fig.
I
3). The object should
be located directly over
the illumination (Fig. 1, 12).
In the next step, take a look through the
eyepiece (Fig. 1, 1) and carefully turn the focus
knob (Fig. 1, 16) until the image appears clear
and sharp.
Now you can select a higher magnification
by slowly removing the Barlow lens (Fig. 1, 3)
from the eyepiece support (Fig. 1, 5). When the
Barlow lens is almost completely pulled out,
the magnification can be increased to –almost
double. If you would like an even higher level of
magnification, insert the 16x eyepiece (Fig. 1,
2) and turn the objective nosepiece (Fig. 1, 8)
to a higher setting (10x or 40x).
Important tip:
The highest magnification is not always the
best for every specimen!
Note:
Each time the magnification changes (eyepiece
or objective change, pulling out the Barlow
lens), the image sharpness must be readjusted
with the focus knob (Fig. 1, 16). When doing
this, make sure to be careful. If you move the
(Fig. 1, microscope stage too quickly, the objective and
under the slide could come into contact and become
damaged!
For transparent objections (e.g. protozoa), on
the other hand, the light shines from below,
through the opening in the microscope stage
and then through the object.
The light travels further through the objective
and eyepiece, where it is also magnified, and
finally goes into the eye. This is transmitted-
light microscopy.
Many microorganisms in water, many plan
components and the smallest animal parts are
already transparent in nature. Others have to
be prepared. We may make them transparent
through a treatment or penetration with the
right materials (media), or by taking the thinnest
slices from them (using our hand or a specimen
slicer), and then examine them. You can read
more about this in the following sections.
How do I make thin specimen slices?
Only do this with the supervision of your parents
or another adult.
As I already pointed out, the thinnest slices
possible are taken from an object. In order
to get the best results, we need some wax or
paraffin. It is best if you get a candle. Place
the wax in a pot and heat it carefully over a low
burner. Now, dip the object in the liquid wax a
few times. Then, let the wax get hard. Using the
specimen slicer (Fig. 1,19) or a knife/scalpel,
cut the smallest slices from the object that is
covered with wax. These slices are to be laid on
a slide and covered with a cover slip.
How do I make my own specimens?
Take the object that you want to observe and
place it on a glass slide. Then, add a few drops
of distilled water on the object (Fig. 7) using
a pipette (Fig. 1, 19). Now, place a cover slip
vertically at the edge of the drop of water, so
that the water runs along the edge of the cover
slip. Then, slowly lower the cover slip over the
water drops (Fig. 8).
Fig. 7
Note:
The included glue "gum media" (Fig. 1, 18) is
used to make permanent prepared specimens.
Use this in place of the distilled water. If you
want to keep the object in place on the slide
permanently, use the gum media.
GB
Fig. 8
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