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6 Photomicrographic Procedure
To ensure vibration free operation, set the microscope on a sturdy vibration
free table or a bench with a vibration proof device.
Pull the optical path selection lever of the trinocular eyepiece tube all the way
out to the limit, the ratio of light entering the observation tube and phototube
will be 20:80.
For the same total magnification, select a combination of the highest possible
objective magnification and lowest possible projection lens magnification to
achieve the utmost image definition and contrast.
To ensure optimal illumination, check the position and centering of the lamp
and position of the condenser.
Select a blue filter for routine application. An additional colour-compensating
filter can be used depending on the colour rendition.
Adjustment of the field diaphragm is important for the purpose of limiting
extraneous light that may cause flare and lower the contrast. Stop down the
diaphragm to achieve an illuminated area slightly larger than that of the field
of view.
A change to depth of focus, contrast and resolution of the image is attainable
with an aperture setting that is 2/3 of the objective N.A.
For photomicrographic procedures, refer to the manual of the specific camera
being used.
Note:
The correlation between the position of the polarizing plate and
photomicrographic devices should not be of any concern to the user, given
that the intermediate tube contains a built-in depolarizer.
