No matter how careful you are, sooner or later dirt will appear on every lens. This is where a handheld air pump
comes in handy.
When cleaning optical lenses, before using lens cleaning fluid and/or microfibre wipes, it is a good idea to blow off any air-removable dust particles from the surfaces. Unfortunately, dust particles vary in material, and if not removed, can become embedded in the anti-reflective coating of the optics, causing unpleasant glare and degrading image quality.
Two tools are commonly used to remove dust particles: an air pump or a compressed air spray. The latter, however, should only be used with good quality spray that does not contain dirt. The air pump or pear pump is always at hand, never runs out, and is handy for optical cleaning.