MicroscopyUsing a Microscope Properly

  Parts of the Microscope

Magnification• Your microscope has 3 magnifications: Scanning,

Low and High.• Each objective has a magnification written on it. • In addition, the ocular lens (eyepiece) has a

magnification. • The total magnification =

ocular x objective

Calculating Magnification

Magnification Ocular lens Total Magnification

Scanning 4x 10x 40x

Low Power 10x 10x 100x

High Power 40x 10x 400x

Microscope Procedures1. All backpacks and other items must be cleared

from the aisles.2. Always carry microscopes with two hands! One

hand on the arm and the other under the base.3. Plug your microscope in to your table.4. Always start and end with the Scanning Objective.5. Always wrap electric cords before returning them

to the cabinet.6. Microscopes should be stored with the Scanning

Objective clicked into place.

Focusing on Specimens1. Always start with the scanning objective. Odds are, you will be able to see something on this setting. Use the Coarse Knob to focus, image may be small at this magnification, but you won't be able to find it on the higher powers without this first step. Do not use stage clips, try moving the slide around until you find something.2. Once you've focused on Scanning, switch to Low Power. Use the Coarse Knob to refocus. Again, if you haven't focused on this level, you will not be able to move to the next level.

Using High Power1. Now switch to High Power. At this point, ONLY use the Fine Adjustment Knob to focus specimens.2. If the specimen is too light or too dark, try adjusting the diaphragm.3. If you see a line in your viewing field, try twisting the eyepiece, the line should move. That's because its a pointer, and is useful for pointing out things to your lab partner or teacher.

ACTIVITY 3-1 PART 1

Observation of Your Own Hair

Observing your own hair cuticle1. Get a clean glass slide. 2. Wipe a thin layer of nail polish on the slide the

length and width of a cover slip.3. Either pull out or cut a hair from your head.4. Slowly lower the hair into the nail polish being

careful not to wiggle the hair back and forth.5. Wait 10 minutes to remove the hair.6. Observe the slide under the three

magnifications 7. Sketch your cuticle