There are several reasons why you should use the coarse focus knob only with the 4x objective and not with the high power objectives. Reason 1: protect the objectives from damage If you focus the high power objectives with the coarse focus knob, then you risk slamming the objective into the slide, risking the damage of both.
Reason 1: protect the objectives from damage If you focus the high power objectives with the coarse focus knob, then you risk slamming the objective into the slide, risking the damage of both. Some high power objectives are spring-loaded, with a front-part that retracts when touched by the slide.
The coarse focus knob can be used to adjust the focus when using any of the objective lenses. Once focus is achieved at one magnification, a higher-power objective lens can be rotated into position without fear of striking the slide.
The objective at the highest position, the 4x objective should of course not touch the slide. Close the condenser and looking through the eyepiece lower the stage using the coarse focus until you see a clear image. Only rotate the coarse focus into one direction and stop when you see a clear image.
The reason is that if there is immersion oil on the slide, then objective should be lowered into the oil from the top and not from the side, to prevent smearing of the immersion oil all over the place. Use the coarse focus only with the 4x low power objective.
The reason is that if there is immersion oil on the slide, then objective should be lowered into the oil from the top and not from the side, to prevent smearing of the immersion oil all over the place. Use the coarse focus only with the 4x low power objective. You can use the fine focus knob with all objectives.
Why is it important to not use coarse knob on high magnification? Coarse and fine adjustment The coarse adjustment knob should only be used with the lowest power objective lens. Using the coarse focus with higher lenses may result in crashing the lens into the slide.
to adjust the image at each of the magnifications. CAUTION: NEVER, EVER, use the coarse adjustment knob with the high power objective. This could break the lens.
Never use the coarse adjustment knob when focusing with the high-power or oil immersion objectives in place as this can damage the objective or the slide.
The fine-adjustment knob on a light microscope focuses by moving the lens slowly and is used to focus on the specimen more clearly. It is used with the high-power objective lenses. The course-adjustment knob focuses by moving the lens quickly and is used to find the specimen your are observing.
The body tube of the microscope should not be lowered while looking through the ocular lens because you do not want to lower the body tube too much and have it crack the slide. to move the body tube in order to focus on the specimen.
COARSE ADJUSTMENT KNOB — A rapid control which allows for quick focusing by moving the objective lens or stage up and down. It is used for initial focusing.
Microscope Short Answer ReviewABWhich two structures on the microscope will you use to focus on your specimen?Coarse Adjustment Knob & Fine Adjustment KnobWhy should you never use the coarse adjustment knob on high power?It will crack the slide.13 more rows
Course adjustment knob – Use this knob to focus your slide when using the lowest power objective (10x). IMPORTANT: Never use the course adjustment knob when focusing the medium- or high-power objective! This can break the slide and scratch the objective lens!
DO NOT USE THE COARSE ADJUSTMENT WITH THE OIL IMMERSION OBJECTIVE. ONLY USE THE FINE OBJECTIVE, BECAUSE YOU CAN BREAK THE LENS.
fine adjustment knobOnce the oil immersion (100X) objective lens is in position over the specimen, focus using only the fine adjustment knob.
13. Use ONLY the fine adjustment knob to focus on high power. NEVER USE THE COARSE FOCUS KNOB ON HIGH POWER! The high power lens should be very close to your slide when in proper focus.