what is the function of the fine adjustment knob on a compound light microscope?
The fine adjustment knob on a compound light microscope is used to make small, precise adjustments to the focus of the microscope. It is typically a smaller knob located on the side of the coarse adjustment knob. The main function of the fine adjustment knob is to bring the specimen into sharp focus after using the coarse adjustment knob to approximate the focus.
To use the fine adjustment knob, follow these steps:
1. Start by placing a slide with a specimen on the stage of the microscope and lower the stage using the coarse adjustment knob until the objective lens is close to the slide.
2. Look through the eyepiece and use the coarse adjustment knob to roughly focus on the specimen. This will result in a somewhat focused image, but not perfectly sharp.
3. Once you have reached this point, use the fine adjustment knob to make small, delicate adjustments to the focus. Gently turn the fine adjustment knob until the specimen becomes sharply in focus.
It's important to note that the fine adjustment knob should be used only after the coarse adjustment knob has been used to get the specimen close to focus. The fine adjustment knob should be handled with care to prevent accidental over-focusing, which can damage the microscope or specimen.