Zeiss 35 mm SLR Camera, Руководство по эксплуатации

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Photomicrography with OPERATION
35 mm SLR cameras Image section/Exposure functions Carl Zeiss
B 40-046 e 03/99 3-7
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If the structures of microprism ring and split image indicator are not seen in focus, attach the
special eyepiece for eyeglass wearers to the viewfinder.
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Fine object structures and details can be focused in accordance with the image in the clear glass areas
of the split image indicator.
However, this requires some practice because photomicrographic cameras have different pupil
positions and sizes than standard camera lenses. Therefore, the clear glass areas of the split image
indicator in the center of the focusing screen are dark when you look into the center of the
viewfinder.
We would therefore recommend you not to look into the center of the viewfinder: depending on the
position of the split image edge, move your eye upwards / downwards or obliquely upwards /
obliquely downwards. An image will then be seen in one field of the split image indicator, while the
other field remains dark.
The fine object structures and details can then be focused in the field of the split image indicator with
the visible image.
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Focusing screens with matte area and central clear glass spot with reticle are ideal for the
setting and focusing of the image section.
Some camera manufacturers offer such a changeable screen.
3.2.6 Exposure Functions
35 mm SLR cameras with TTL (Through The Lens) metering
These 35 mm SLR cameras permit the following metering modes: center-weighted averaging, spot
metering and multiple-area metering. Each of these metering modes permits selection between different
exposure modes, e.g.
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Automatic exposure control:
the camera automatically selects the optimum combination of exposure time and aperture value
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Automatic exposure mode with preselected shutter speed:
the camera automatically selects the aperture value for a desired shutter speed depending on the image
brightness.
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Automatic exposure mode with preselected aperture:
the camera automatically selects the shutter speed for the desired aperture value depending on the
image brightness.
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Exposure after manual exposure alignment with preselected aperture:
depending on the image brightness, the shutter speed is matched for a desired aperture by turning the
shutter speed knob until zero alignment of an indicator (e.g. pointer on indicator).
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Exposure after manually set exposure time and B/T function.
The measuring range of 35 mm SLR cameras is determined by the ranges of exposure values (EV),
shutter speed and film sensitivity in combination with the aperture range of the camera lens.