Microscope Skills- Forensic Science/CSI
- Review proper handling and care of microscopes.
- Locate and name parts of your microscope.
- Understand how an image moves and is magnified when viewing through a scope.
- Explain the function of each component on the scope.
- Calculate total magnification of a compound microscope.
- Compound light microscope
- Prepared slide
- Lens paper/Kim Wipes
- Cover Slide
Part A- Proper Care of the Microscope
- Use both hands to carry the microscope. Keep the instrument upright; oculars sometimes fall out of inverted microscopes.
- Use lens paper to clean all exposed glass in the optical and illumination systems of your microscope before and after each use. Remove all immersion oil. Wipe any fingerprints or mascara off the lenses.
- Never remove parts of the microscope without prior approval of you instructor.
- Never use the coarse adjustment knob to decrease the space between the objective lens and your specimen while looking through the instrument. Instead, watch the procedure from the side of the microscope. By watching as you turn the coarse adjustment knob, you can prevent abrasive contact between the lens and the slide.
- When you are finished with your microscope, maximize the distance between the lens and the stage, remove the slide, clean all surfaces, clean the lenses with the lens paper, put the lowest power in the observation position, center the mechanical stage, and wrap the electrical cord loosely around the base. Cover the microscope and return it to the designated space.
Part B- Components of Compound Microscopes
- Correctly pick up a microscope and carry it back to your desk.
- Sketch the compound microscope following the drawing guidelines.
- Label the following
- Ocular lens
- Fine adjustment knob
- Coarse adjustment knob
- Diaphragm / Condenser
- Light Source
- Clips or Mechanical Stage Control
- Objective Lens
Part C- Letter “e”/using the microscope
- Cut out a small lower case “e” from the newspaper
- Place the “e” onto a clean slide. The “e” should be positioned right side up and in the middle of the stage.
- Carefully cover the “e” with a cover slip.
- Draw a micrograph of the letter “e” as it appears to your naked eye.Draw a second micrograph as it seems to be positioned on the lowest powered lens. Title the diagrams and include the magnification.
- While watching from the side of the microscope, use the mechanical stage control knobs to move the slide to your right. Re-center the slide. Now look through the lenses and move the stage to the right.
- Re-center the slide. While watching from the side, move the stage away from you. Re-center again and observe through the oculars while moving the stage away.
- The ______lens is the one nearest the observer’s eye.
- If my objective lens is set at 45x, what is my total magnification?
- (T/F) A compound microscope contains 2 or more sets of lenses.
- (T/F) To save time, look through the microscope and rapidly bring the objective lens and specimen together by rotating the coarse adjustment knob.
- This can be used to remove oil and smears from the glass components of the microscope.
- If I move my stage right, which direction does the image on the slide move?
- Create a table that includes the objective lenses of your microscope and the total magnification of each lens. Don’t forget to title your table.
- What does the magnification mean?
- If I move my stage to away from myself, my specimen appears to move in this direction.
Microscope lab Write-Up
- State the reason(s) for performing this exercise and how the lab addresses this.
- Briefly outline the main tips for handling/caring for a microscope
- “write see handout”
- “write see handout”
- Labeled Diagram of microscope
- 2 Micrographs of “e”
- Answer all questions
- P- restate the purpose
- H- address the hypothesis (not needed in this lab)
- A- applications –apply the lab to the real world or real experiences
- L- What did you learn?
- E- What are the sources of error? (there are always more than one)