A clean microscope is essential for clear images and reliable results. This guide shows you how to maintain your microscope correctly – from daily cleaning routines to recognizing signs when professional service is needed. Learn how to detect contamination, handle oil immersion objectives, and how to transport or store your microscope safely. Whether you're working in life sciences or materials research, these practices help protect your optics, extend equipment life, and ensure consistent results over time.

Key learnings:

• Using the right cleaning tools and methods prevents damage to sensitive optical components.
• Detection of dirt and a regular maintenance improve image quality, extend the microscope's lifespan, and minimize the instrument's downtime.
• Correct handling of oil immersion and the proper transport/storage are critical for long-term performance.
• Understanding the specific cleaning techniques for different optical surfaces enhances cleaning results.

Even small amounts of dust, oil, or residues will degrade the image quality. Here’s how you can spot contamination early:

• Visual inspection with oblique illumination
  Use a light source to detect smudges or dust on objectives, eyepieces, and condenser lenses.
• Check the image
  Blurred zones, ghosting, or low contrast are common signs of contamination.
• Use cleaned slides and cover glasses
  If spots appear while observing a clean field, they may be on the optics (stationary) or the slide (moving). Slides should be stored in 70% ethanol and wiped dry before use. As the glass type used for slides will corrode, it is not advisable to stock them in large amounts (shelf life is approx. 2 years). Cover glasses have an almost unlimited lifetime. Also store them in 70% ethanol.
• Carefully rotate the components
  Rotate objectives or cameras slightly. Move the specimen slide while focusing on its upper and lower surfaces. Adjust the condenser up and down, swivel the front lens if possible. Dirt will move with the affected component.
  Remember: dirt inside the camera remains stationary.

Pro tip: Never clean surfaces where you guess the contamination could be. Confirm their location first – then clean only what’s needed.