107
Calibration:
Align the stage micrometer and the graticule
parallel to each other by rotating the stage or
the eyepiece and adjust the zero marks of both
scales to exactly the same height.
Read how many scale divisions of the stage
micrometer correspond to how many on the
microscope scale (graticule) and divide the two
values.
Example:
If 1.220 mm of the stage micrometer corresponds
to 50 divisions of the measurement scale, the
micrometer value is 1.220 : 50 = 0.0244 mm = 24.4
µ
m. For extremely low objective magnifications
it may be that only part of the measurement
scale can be used for calibration.
Imp ortant: If using a Variotube or variable tube
factor:
Remember to take the additional magnification
value into consideration! We strongly
recommend you calibrate each objective
separately instead of extrapolating the
micrometer values of the other objectives from
the calibration of one objective. Measurement
errors may occur if the eyepiece is not pushed
into the tube as far as the stop.
Particularly large object structures can also be
measured on the stage with the verniers
(0.1 mm); the distance to be measured could
be calculated from a combined x and y
measurement.
Fig. 68
Graticule division in eyepiece (left) and image of the
stage micrometer (right)
