How to Use a Compound Microscope

Procedure

1 Uncover the microscope, unwrap the cord, and plug it in.

2 Clean all glass surfaces with lens paper. Start with the eyepiece, then do the objectives, the substage mirror or illuminator, and end with the stage window.

3 Turn on the light (or adjust the mirror so that the light shines through the stage window). Adjust the diaphragm under the stage so that a medium amount of light gets through. Adjust the fine focus knob to a middle position.

4 Place the slide on the stage, with a slide clip holding down each side of the slide. Center the specimen on the slide over the stage window.

5 Using the low power objective, focus with coarse
adjustment. Start with the objective as close to the
slide as possible and focus away from the slide. Most
microscopes need less than 1/4 of a turn to focus.

6 Before turning to a higher power, make sure there is
something worthwhile to look at and center the
specimen in the middle of the field.

7 Without changing the focus adjustment, change to the
next highest objective (the centered specimen should
be in view and should be almost in focus). Now focus
with the fine adjustment knob.

Repeat Steps 6 and 7 up to the highest power (except
for oil immersion objectives).

8 Clean up! Return to low power objective before taking
off the slide. Clean and dry the stage and objectives,
turn off the light, and wrap the cord neatly around the
base of the microscope. Replace the cover.