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Observe how a microscope can be focused on different levels of an object from its top to its bottom surface.

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Introduction

Liban Ahmed                                   Experiment 3                           September 20, 2003

Depth of Field

Purpose

Observe how a microscope can be focused on different levels of an object from its top to its bottom surface.

Hypothesis

The microscope can be adjusted and utilized to focus on objects that have different depths. The microscope has different depths of fields depending of the magnification. The higher the magnification the less depth of field. The lower the magnification, the higher the depth of field.

Materials

  • Prepared slide of 1cm square pieces of several types of cloth
  • Microscope

Procedure

  1. Brought a microscope to the lab area making sure to use both hands to carry the microscope and that the cord was not dangling.
...read more.

Middle

Rotated the nosepiece to the low-power objective lens and carefully focused on the image. Recorded observations.Rotated the nosepiece to the medium-power objective lens and carefully focused on the image.Recorded observations.Rotated the nosepiece to the high-power objective lens and carefully focused on the image.Recorded observations.Removed the slide.Cleaned up the lab area and placed the equipment in the designated places.

Observations

Observations of the Slide under the Low, Medium, and High Magnifications

  1. Under the low-power magnification, the red thread seemed to be on the top position. Three threads seemed to be in focus under the low-power magnification and all three threads were simultaneously in focus.
  1. Under the medium-power magnification, the red thread seemed to be on the top position.
...read more.

Conclusion

Text Questions

  1. The eye focuses on one object at a distance; however, it has to adjust and focus if the individual looks at a closer or more distant object. Therefore, the eye is continuously adjusting to focus on close and distant objects. An individual cannot focus on a near and distant object at once.
  1. An object being observed under a microscope must be thin to allow light from the diaphragm to pass through the object thus allowing the object to be magnified. An object must also be thin to allow the observation of detail and texture. If no light passes through the object, the object will leave a dark shadow and there will not be a presence of detail or texture.  

...read more.

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