CARDINAL RULES FOR MICROSCOPE USE:
| light path base power switch lamp and housing lamp rheostat arm stage iris diaphragm & lever (Here is how it works.) condenser condenser positioning knob mechanical stage, retaining screws mech stage positioning knobs |
slide
retainer
and
thumb knob coarse focus (show dir to lower) fine focus objectives parfocal objective lenses (when one objective is in focus, all should be close to in focus) achromatic coating (prevents "rainbow edges.") nosepiece or turret optical head optical head retaining screw oculars binocular focus ( L adjustable ocular ) interpupillary distance |
Here is a view of the left side view of the microscope .
NOTE ESPECIALLY:
| lamp rheostat | Use the rheostat setting at as low a setting which produces adequate lighting (around 5-7). Too high a setting generates excessive heat and reduces the life of the $50 bulb. | |
| iris diaphragm lever | Move side to side while viewing through the ocular. What
happens? Here is an excellent animation of the action
of
the iris diaphragm in adjusting the aperature and the rheostat.
Here are the stages of adjusting the iris diaphragm. ![]() |
|
| Coarse and Fine focus | Which direction do you rotate the coarse focus knob to lower
the stage?
Memorize this direction. Use coarse focus only
with the 4x objective.
Note: the fine focus moves the stage almost imperceptibly |
|
| Nosepiece (turret) | With the stage lowered, rotate the nose piece so that each of the objectives is successively pointing down, clicking when the objective is in proper position | |
| Ocular | What is the magnifying power of the ocular? What would the
power of
magnification be if you were using the 4x objective with this ocular?
Note that the left ocular is adjustable. Begin with it set on zero, and adjust if necessary so that the image is focused for both eyes. |