Nikon ECLIPSE Ei Instructions Manual page 56

Using the objective of a higher magnification for

observation
First, use the 10x objective to focus on the specimen, and
then change it to the desired objective and rotate the fine
focus knob to precisely focus on the specimen.
When operating the focus knob while using the
objective of a higher magnification, care must
be taken to prevent the slide glass from
touching the objective. When you raise the
stage using the coarse focus knob, look at the
gap between the upper surface of the specimen
and the front of the objective from the side.
Using working distances

The stage can be raised by using the working distance
(→ See Section 3.10, "Microscope Terminology".) of the
objective.
While looking at the microscope from the side, rotate the
coarse focus knob with care to bring the specimen close to
the objective. Then, when the distance between the
specimen and the front of the objective becomes slightly
smaller than the working distance, take your hands off the
coarse focus knob. The specimen is now almost in focus.
Look into the eyepieces and rotate the fine focus knob in
the direction that lowers the stage to precisely focus on the
specimen.
Focusing by switching the objective from 40x to 10x

Swing the 40x objective into the optical path. While looking at the microscope from the side, rotate the coarse
focus knob until the specimen almost touches the objective (about 0.5 mm apart from the front of the
objective). Switch to the 10x objective, look into the eyepieces, and rotate the fine focus knob slightly to find
the focal point. Be careful not to hit the objective with the specimen.
Chapter 3 Detailed Explanation
54