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2.3: Focusing the Microscope

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    1. Rotate the nosepiece so that the scanning objective is over the light source.
    2. Obtain a letter e slide from the instructor. Use the stage clip to secure the slide onto the mechanical stage. Use the stage adjustment knobs to bring the letter e under the scan objective and over the light source.
    3. Use the coarse adjustment knob to bring the letter e into focus. Once the letter e is in focus, the image can be made sharper by using the fine adjustment knob.

      Draw the “e” as you observe it with the microscope and describe the principle of inversion.


    4. Move the slide so that the pointer is on the letter e. Rotate the low power objective lens into place and use the fine adjustment knob to bring the slide into focus.
    5. Focus using the high power objective lens and the fine adjustment knob. Do not use the coarse adjustment knob with the high power objective lens. Record observations on high power.
    6. Return the slide and use the revolving nose piece to return to the scan objective lens.

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