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6
4.
Adjust fine focus controls until specimen is in sharp focus.
5.
Adjust diopter for difference in eyesight.
a.
Using right eye, peer into the right eyepiece tube. Adjust sharpness of image by utilizing fine focus
controls.
b.
Using left eye, peer into the left eyepiece tube. Adjust sharpness of image by turning diopter
adjustment located on left eyepiece tube.
6.
Adjusting the aperture (opening) of iris diaphragm.
Iris diaphragm should not be used to control the brightness of illumination, use light intensity control
knob to adjust light level. Iris diaphragms are designed to help achieve high resolution of specimen and
provide contrast in the image. Smaller apertures will deliver higher contrast to image. However, closing
aperture too much will reduce resolution. Experimentation is the best method of determining the correct
opening of diaphragm. Some suggested openings for iris diaphragm are:
OBJECTIVE
DIAPHRAGM OPENING
4x
1/8 open
(MIN)
10x
1/8 to 1/4 open
40x
1/4 to 1/2 open
100x
1/2 to 3/4 open (MAX)
7.
Changing magnification.
a.
Rotate revolving nosepiece to position 10x objective into optical path.
b.
This microscope has been parfocalized, which allows changes from one objective to another while
requiring only a slight adjustment of the fine focus controls.
c.
When changing to the 40x and 100x objective lens, care must be exercised in order to prevent
damaging the front lens element and specimen slide.
d.
In order to obtain maximum resolution of the 100x oil immersion lens, it is necessary to apply
immersion oil between the coverglass of slide and front lens of the objective.
1)
Use of a very small amount of immersion oil is required. Only the very tip of the lens
should ever come in contact with the immersion oil. Oil should not come in contact
with the white sealant ring on the objective. Excess use of immersion oil will ruin your
objective and void your warranty.
2)
All air bubbles must be removed from between lens and slide by rotating nosepiece back and
forth.
8.
When finished viewing, all parts that come in contact with oil must be cleaned. Failure to do so could
permanently damage the 100x oil immersion objective lens. Use of Windex to clean immersion oil off
lens surfaces is recommended.
9.
Coarse focus tension adjustment.
a.
Tension adjustment knob is located between stand and coarse focus knob of microscope, on the
right side.
b.
To tighten tension of coarse focus knobs, turn control in a counter-clockwise direction. It is
advisable to leave controls as loose as possible, tightening only enough to keep stage from drifting
down and out of focus. To loosen tension, turn control in clockwise direction.
Objective Specification Chart
Objective
N.A.
Color Code Ring Field of View
Magnification
Din 4X
0.10
Red
4.5mm
40X
Din 10X
0.25
Yellow
1.8mm
100X
Din 40X
0.65
Blue
0.45mm
400X
Din 100X
1.25
White
0.18mm
1000X