How to clean and maintain lens filters?

Why do you need to clean the lens filter so carefully?
Dust is the enemy of imaging: Even tiny dust particles that are invisible to the naked eye, once attached to the surface of the filter, can easily cause diffraction under strong light, resulting in flare, ghosting and other problems in the photo, seriously affecting the image quality.
Grease stains corrode the mirror surface: Grease, cosmetics and other substances on the fingers will corrode the coating on the surface of the filter, reduce light transmittance and affect color reproduction.
Extend the service life of the filter: Regular cleaning can effectively remove stains, prevent scratches on the surface of the filter, extend its service life, and thus save the cost of replacing the filter.

Selection and use of cleaning tools
Blowing balloon: Choose a professional blowing balloon for lens cleaning, which has a soft airflow and will not damage the filter.
Lens cleaning fluid: Use a special lens cleaning fluid, which has a mild composition and will not corrode the lens surface.
Lens paper: Lens paper is soft in texture, absorbs water well, and will not leave fibers.
Lens pen: For stubborn stains, you can use a lens pen to gently wipe, but be careful not to use excessive force.

Detailed explanation of cleaning steps
Keep away from dust sources: Before cleaning, choose a clean environment to prevent dust from attaching to the filter again.
Blow away floating dust: Use a blower to gently blow away dust particles on the surface of the filter. Pay attention to the angle to avoid blowing dust into the lens.
Drop cleaning solution: Drop a small drop of cleaning solution in the center of the lens paper, not too much.
Spiral wipe: Gently wipe in a spiral from the center of the filter to the outside, do not wipe back and forth to avoid scratching the filter.
Replace lens paper: When the lens paper becomes dirty, replace it with a new lens paper in time.
Edge treatment: Gently wipe the edge of the filter with clean lens paper to ensure that there is no residual stain.
Natural air drying: Place the filter in a ventilated and cool place and let it dry naturally.

Storage and maintenance of filters
Dry environment: Store the filter in a dry moisture-proof box to avoid moisture that causes mold growth.
Store separately: Each filter should be stored separately to avoid scratches caused by friction with each other.
Avoid direct sunlight: Prolonged exposure to sunlight will accelerate the aging of the filter.
Regular inspection: Check the filter regularly for damage and replace damaged filters in time.

Handling in special circumstances
Water droplets or oil stains: Blow dry with a hair dryer on the cold air setting, or wipe gently with dry lens paper.
Fingerprints: Wipe gently with lens cleaning fluid and lens paper, and be careful not to use too much force.
Salt spray corrosion: If the filter is used in an environment with high salt content such as the seaside, it should be rinsed with clean water in time and wiped clean with lens cleaning fluid.