In a compound microscope, which part do you adjust to sharpen focus if the image is out of focus?

In a compound microscope, which part do you adjust to sharpen focus if the image is out of focus?

• A. mirror
• B. eyepiece
• C. fine adjustment knob
• D. coarse adjustment knob

Answer: (C)

Sharpening focus on a compound microscope relies on small, precise moves. When the image is blurry, you first use the coarse adjustment knob to bring the specimen into general view, then switch to the fine adjustment knob to make tiny, controlled movements that bring the image into crisp focus. The coarse knob handles big changes and can overshoot if you try to fine-tune with it. The eyepiece simply magnifies the image, and the mirror provides illumination—neither directly sharpens the image. So, the best tool for refining and sharpening focus is the fine adjustment knob.

Sharpening focus on a compound microscope relies on small, precise moves. When the image is blurry, you first use the coarse adjustment knob to bring the specimen into general view, then switch to the fine adjustment knob to make tiny, controlled movements that bring the image into crisp focus. The coarse knob handles big changes and can overshoot if you try to fine-tune with it. The eyepiece simply magnifies the image, and the mirror provides illumination—neither directly sharpens the image. So, the best tool for refining and sharpening focus is the fine adjustment knob.