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8. Operation
Attention:
The aperture diaphragm in the illumination light
path is not for setting the image brightness. Only
the rotary brightness adjustment knob or the
neutral density filter should be used for this.
An aperture diaphragm in the objective is
normally fully opened. The reduction in image
brightness caused by stopping down results in:
Greater depth of field
Less coverglass sensitivity
Suitability for darkfield
Change in contrast
8.9 Field diaphragm
The field diaphragm (46.5) protects the
specimen from unnecessary warming and keeps
all light not required for image formation away
from the object to enable greater contrast. It is
therefore only opened just wide enough to
illuminate the viewed or photographed object
field. A change in magnification therefore
always necessitates matching of the field
diaphragm.
Color-coded Condenser
The color markings on the condenser (46.2)
correspond to the color rings of the objectives.
When changing objectives, a suitable aperture
diaphragm setting can easily be found by setting
it to the matching color marking (corresponds to
2/3 of the objective-side aperture).
Fig. 46 CL/PH condenser
1Slot for light rings, etc.
2Color coding
3Aperture diaphragm
4Filter holder
5Field diaphragm
2
3
1
4
5