Cleaning the microscope

Cleaning procedure:

• Blow all loose dust particles away with a dust blower.
• Remove all water-soluble dirt with distilled water. If this is unsuccessful repeat using a solution of diluted washing-up liquid.
• Remove any remaining residue with a dry cotton swab, but breathe on the surface first to generate a film of moisture.
• To remove oily dirt, use a solution of dilute washing-up liquid initially. If this does not produce a satisfactory result, repeat the cleaning using a solvent (Optical Cleaning Solution L, petroleum ether).
• Greasy dirt must always be removed using a solvent.
• Place the objectives, eyepieces and cameras on a dust-free surface (e.g. fresh aluminum foil).
• All other optical components to be cleaned should be as accessible as possible.
• Dip the cotton swab into the cleaning solution and shake off excess liquid.
• An excess of liquid in a cotton bud will flow over the rim of the lens and attack the lens cement. This may consequently lead to the removal of the cement between bonded components.
• The solvent should remove as much dirt as possible. In order to increase the retention time of volatile organic solvents in the cotton bud, some users chill the solvent (–10ºC to –20ºC). Chilled solvents have a disadvantage: due to their low temperature, condensation may form on the lens surface and leave a residue.
• A more suitable way to improve the retention time of a solvent is to add isopropanol, for example.