How to clean dirty photographic lens?

The photographic lens can be cleaned by the following methods if it is dirty:
Air blow cleaning: Use a handheld air blow to remove dust from the camera filter and lens surface. When operating, blow the air outlet downwards several times to remove the dust inside, then hold the camera or lens and tilt it downwards at a 45 degree angle to blow away the dust on the surface. Be careful not to probe too deeply into the camera mount and avoid direct contact with the dustproof glass. ‌
Mirror brush cleaning: If air blowing cannot remove the dust on the surface of the lens, you can use a mirror brush to gently sweep it away. Do not touch the bristles directly with your hands.
Contact cleaning: For stubborn stains on the surface of the filter or lens, such as finger marks, liquid residues, etc., a grease free cotton swab or dust-free cloth can be used to wipe and clean with high-purity alcohol. The specific operation is to spiral wipe from the center outward, being careful not to squeeze the surface of the lens forcefully to avoid damaging the vulnerable coating.
Lens paper cleaning: For more stubborn stains, lens paper can be used. Use lens paper that has just been opened and is in a moist state, slowly spiral wipe from the center of the lens outward in the same direction. Be careful not to use hard paper, tissues, or napkins, as these products may contain abrasive wood pulp that can damage the lens coating.
Methods to prevent lens mold and maintain lens cleanliness:
Moisture proof treatment: Avoid storing the camera in wooden or metal cabinets, as these materials are prone to moisture absorption. Cameras should not be stored in leather cases, suitcases, or towels, as leather and cotton fabrics are prone to moisture absorption. It is recommended to use a professional moisture-proof box or sealed box with desiccant to prevent the lens from getting moldy. ‌
Regular cleaning: Regularly using an air blower, mirror brush, and cleaning solution to clean the lens can effectively prevent the accumulation of dust and stains.
By using the above methods, it is possible to effectively clean and maintain the photographic lens, extend its lifespan, and maintain good shooting results.