Zeiss 35 mm SLR Camera, Руководство по эксплуатации

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OPERATION Photomicrography with
Carl Zeiss Selection of color temperature/film 35 mm SLR cameras
3-6 B 40-046 e 03/99
Example 1:
The correction value +1 means that one exposure value (+ 1 EV) is added to the exposure time in
brightfield recommended by the automatic exposure control for zero setting (i.e. twice the exposure
time: negatives will be denser, slides and Polaroid photos brighter).
The correction value -2 means that two exposure values (-2 EV) are subtracted from the exposure time
for darkfield / fluorescence recommended by the automatic exposure control for zero setting (i.e.
exposure time is reduced by one quarter: negatives will be brighter, slides and Polaroid photos denser).
Most 35 mm SLR cameras feature an exposure correction ring which allows the exposure time to be
corrected in steps of 1/3 EV within a range b2 EV and -2 EV
Furthermore, some SLR cameras permit exposure bracketing to be made. When the exposure has been
triggered, three photos are taken with different correction values - the correction value is automatically
changed by -1 EV from exposure to exposure.
Example 2:
The exposure correction ring has been set to +1. The first photo is exposed with +1 EV, the second with
±
0 EV and the third with -1 EV.
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For the setting of exposure correction and exposure bracketing please see the operating
instructions of the used 35 mm SLR camera!
3.2.5 Setting and Focusing of Image Section
−
Via binocular tube;
the section of the microscope object set in accordance with the photo reticle is imaged on the film in
focus when the focusing cross and the specimen are clearly defined simultaneously. To achieve
correct focusing even with low objective magnifications, it is recommended to use the 3x12 B
monocular, focused to infinity, as an adjusting aid (monocular attached to eyepiece with photo
reticle).
☞
Insert photo reticle as described in section 2.1.2.1 and focus eyepieces in binocular tube in
accordance with 2.1.2.2.
−
Via the usual focusing screen in the viewfinder of the SLR camera;
the image section on the focusing screen is slightly smaller than the image section on the film.
Therefore, all the image details visible on the focusing screen are also visible on the film.
The set image section is sharply imaged on the film if the structures of the microprism collar with split
image indicator and the image of the microscope object in the matte area or microprism collar are in
focus at the same time.
☞
Fine object structures and details may be lost because of the granularity of the matte area and
the microprism collar.
Object details which can still be well recognized should therefore be selected for focusing.