The objective lens should be kept clean not only for good optical images but also to minimise laser reflections which will degrade the CAM1 performance. Remember that this is a precision optic and should be cleaned with great care. First gently brush away any dust using a soft brush or a piece of gauze. To remove fingerprints or grease, gently clean using a lens tissue lightly moistened with lens cleaner, or pure alcohol ( ethyl alcohol or methyl alcohol ). Observe sufficient caution when handling methanol & ethanol.
Also remember that the CAM1 contains carefully aligned optics so always handle with care!
When not in use cover and store in a place free from moisture and fungus.