Microscope NotesThe compound microscope is a useful tool for magnifying objects up to as much as 1000 times their normal size. Using the microscope takes lots of practice. Follow the procedures below both to get the best results and to avoid damaging the equipment. Show
Field of ViewThe field of view is largest on the lowest power objective. When you switch to a higher power, the field of view closes in towards the center. You will see more of an object on low power. Therefore, it is best to find an object on low power, center it, and then switch to the next higher power and repeat. Depth of FocusThe depth of focus is greatest on the lowest power objective. Each time you switch to a higher power, the depth of focus is reduced. Therefore a smaller part of the specimen is in focus at higher power. Again, this makes it easier to find an object on low power, and then switch to higher power after it is in focus. A common exercise to demonstrate depth of focus involves laying three different colored threads one on top of the other. As the observer focuses down, first the top thread comes into focus, then the middle one, and finally the bottom one. On higer power objectives one may go out of focus as another comes into focus. Microscope TroubleshootingProblem #1: The image is upside down and/or backwards.
Problem #2: Everything is dark.
Problem #3: I can't find anything on low power!
Problem #4: When I moved to a higher power, everything disappeared!
Problem #5: The image is blurry on all powers.
Problem #6: The image is blurry only on a particular power.
Microscope DrawingsWhen drawing what you see under the microscope, follow the format shown below. It is important to include a figure label and a subject title above the image. The species name (and common name if there is one) and the magnification at which you were viewing the object should be written below the image. All relevant parts of the drawing should be labelled on the right side of the image using straight lines. Lines should not cross. Drawings should be done in pencil, while labels should be in pen or typed. Remember that total magnification is determined by multiplying the ocular x objective. Viewing Prepared Slides*** Don't hoard slides! You can only view one at a time, so that's all you should be holding. Return it before getting another, and if you break it, tell your instructor so that it can be properly cleaned up and replaced! ***
Making a Wet Mount (Live Prep) Slide
Further InvestigationDigital microscope for Macintosh or Windows Investigating pondwater organisms Powers of 10 (1977 version) Make your own microscope What happens when you switch from low power to high power on a microscope?When you switch to a higher power, the field of view is closes in. You will see more of an object on low power. The depth of focus is greatest on the lowest power objective. Each time you switch to a higher power, the depth of focus is reduced.
When a student uses a compound microscope and switches from low power to high power the field of view will?Terms in this set (12) A student viewing a specimen under low power of a compound light microscope switched to a high power and noticed that the field of view darkened considerably.
Which part of the microscope is used to change from low power to high power?Revolving Nosepiece or Turret: This is the part of the microscope that holds two or more objective lenses and can be rotated to easily change power.
When using a microscope and moving the objective lens from low power to high power?When using a microscope and moving the objective lens from low power to high power, it is important to always: focus with the fine adjustment knob. You may change the contrast of an observed image through the microscope by: moving the iris diaphragm lever.
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