Which action is a proper use of a microscope when observing a slide?

• A. Move the microscope slide around so that the image is in the center of the field of view.
• B. Use only the coarse adjustment knob to focus.
• C. Keep the slide at the edge of the stage.
• D. Turn off the light source when observing.

Answer: (A)

Centering the specimen by moving the slide on the stage keeps the region you want in view as you switch magnifications. This method preserves the alignment of the optics and makes it easy to follow the same area when you go to higher power, which is essential for examining细细 details without losing your place. Start with the lowest magnification to locate the object, use the coarse adjustment to bring it roughly into focus, then apply the fine adjustment to sharpen the image. Illumination should remain on and adjusted for comfortable viewing, and avoid placing the slide at the edge of the stage, which can make the target hard to keep in view. Using only the coarse adjustment is not ideal for focusing, and turning off the light or viewing at the edge of the stage hinders visibility and makes observation impractical.