V Microscope Adjustment
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(6) Adjusting the Exposure Time
Use an ND filter to adjust the illumination for the microscope to a level that yields a suitable
exposure time (generally 1/15 to 1/250 s). You can also adjust the camera sensitivity.
Terms
What is an ND filter?
An ND filter is a filter that affects only the amount of light passed, not the color balance of
the light. For example, an "ND2" filter cuts transmitted light in half, while an "ND16" filter
reduces transmitted light to 1/16th of actual levels.
(7) Effects of Ambient Light
When capturing a dark specimen with a fluorescent microscope, for example, ambient indoor
light may enter the optical path. Accordingly, interior lighting should be darkened for
photomicrography. Place caps on the binocular eyepiece to prevent light from entering through
the eyepiece.
(8) Effects of Vibration
Because photomicrography involves extremely high image resolution, the slightest vibration can
affect image quality. To insulate the microscope from vibration, set it on a solid, stable surface
on a solid floor. Using an anti-vibration table compatible with the microscope will further reduce
the effects of vibration. While actual microphotography is in progress, be careful to avoid
touching the microscope or the desk or stand on which it is positioned.
