Efficiently using a microscope requires one to adhere to a few simple rules that can help ensure your specimens come into clear focus with less stress. Here are three rules to remember when focusing a microscope:

• Start Low and Slow

  Before peering into the eyepiece, move the microscope focus adjustment knob in small, counter-clockwise circles to lower the objective lens. Avoid higher speeds, or jolting the adjustment knob, as this can easily knock the specimen out of focus.

• Enlarge Slowly

  After the objective lens slides down to the lowest point, slowly increase the magnification and move the focus adjustment knob clockwise. This will allow you to find the best focus easily.

• Check All Lenses

  After the specimen is focused under high magnification, double-check all magnifications to make sure that the specimen is in perfect focus at each stage. If they appear blurry or out of focus, repeat the steps and adjust the focus adjustment knob where needed.

Adhering to these three rules can help anyone focus a microscope with ease and maintain a good image quality. It’s important to keep in mind that each objective lens has its own focus adjustment, so be sure to adjust each one according to your specimen. Good luck, and happy magnifying!