it is the function of HPO or the High Power Objective
There are two adjustment knobs (coarse and fine) on a microscope so you can move the stage at two different speeds. The coarse moves a lot per revolution, while the fine adjustment knob moves the stage at such small increments that it is nearly impossible to notice when looking from the side. The coarse adjustment knob should be used to get the stage closer to the lens only while you are looking at the microscope from the side. The fine adjustment knob can be used when you are looking into the microscope because there is a much lower chance of running the stage into the lens and breaking it.
it is used for final focusing.
The function of a microscope's coarse adjustment knob is to improve focus on the object under study by adjusting the lens. Unlike the fine adjustment, coarse adjustment moves the lenses quickly.
With the "coarse" adjustment, the adjustment mechanism causes a large amount of movement in the thing being adjusted with very little movement of the adjusting mechanism. With the "fine" adjustment, the adjustment mechanism causes a small amount of movement in the thing being adjusted with a lot of movement of the adjusting mechanism. Frequently the two adjustments will be two knobs each with different gearing - say on a telescope focus mechanism. The coarse adjustment allows the telescope focus to be moved quickly then the fine adjustment allows the observer to gently bring the focus to be "pin sharp".
It makes the substance you're looking at clear, and not blurry.It basically puts it into focus.Read more: What_does_fine_adjustment_knob_do_on_a_microscope
The coarse adjustment knob elevates the microscope's stage up and down quickly. The fine adjustment knob does the same thing but more slowly and accurately. In other words, the fine adjustment knob should require more revolutions to elevate the stage as much as the coarse adj. knob does.
The Fine Adjustment
fine adjustment knob.
Use a coarse adjustment knob (large movement) to get near, then use the fine adjustment knob (small movement) to fine-tune.
After you adjust the coarse adjustment knob, the fine adjustment knob makes it sharper or clearer.
You should always use the fine adjustment on a microscope when you are focusing on high-power magnifications, typically 400x and above. The fine adjustment allows for precise focusing, which is crucial for observing details without risking damage to the slide or the lens. It is also recommended to use the fine adjustment after initially focusing with the coarse adjustment to enhance clarity.
There are two adjustment knobs (coarse and fine) on a microscope so you can move the stage at two different speeds. The coarse moves a lot per revolution, while the fine adjustment knob moves the stage at such small increments that it is nearly impossible to notice when looking from the side. The coarse adjustment knob should be used to get the stage closer to the lens only while you are looking at the microscope from the side. The fine adjustment knob can be used when you are looking into the microscope because there is a much lower chance of running the stage into the lens and breaking it.
The fine adjustment knob in a microscope is used to make small, precise focusing adjustments to bring the specimen into sharp focus. It allows for fine tuning of the focus after coarse adjustments have been made using the coarse adjustment knob.
You use the fine adjustment to focus in HIGH power with a compound microscpe.
When the "fine" adjustment control does not bring operation into the desired range.
Coarse adjustment
The coarse adjustment (up or down) is used to quickly move closer to or away from the focal point of the specimen. The fine adjustment is then used to fine tune the focus and bring the specimen into clear view.Coarse adjustment means big movements up or down. Fine adjustment means very small movements until the specimen is in focus.