Professions take extreme care with their gear. They keep each lens in a case with foam inserts and polish them after each use. This is more than a habit; it is a ritual. Most camera owners like to clean the lenses themselves to ensure it is done properly and others will assign an apprentice to help. For those beginning here are a few pieces of advice for caring for the equipment, specifically cleaning the camera lenses.
Imagine the camera lens is as fragile as a baby’s ears. No more huffing your breath and rubbing your t-shirt on junior. Use a soft hand pumping blower to remove dust and specks of dirt that it may have acquired. The less you have to touch the lens, the better.
Wiping with a dry microfiber cloth is the next step. The microfiber cloth should be kept in plastic when not in use. Larger fabrics will definitely scratch the glass beyond reasonable repair. Keep a cloth that always stays dry and another for using chemicals.
If there still some stubborn smudge or oil on the glass you can apply a couple drops of lens cleaning solution. Drop it on a microfiber cloth NEVER DROP CHEMICALS DIRECTLY TO THE LENS. Then repeat the wiping process delicately. A lens pen is an alternative solution to applying the liquid to the cloth and wiping which also always the user to be a bit more vigorous with their strokes.
Keep the lens covers on both sides at all times. Unless they are being used by the camera or in cleaning. Checking the covers themselves is also a good practice as they are often not treated with as much care as the lens glass but are the items that come in closest contact with the lenses.
When shooting in tough environments like rain or wind it is advisable to use a filter to protect the glass from real damage. Using a UV filter will also protect from sun exposure on long, hot shoot days as the crew does their work and the camera sits there in focus waiting to record.
Since the lens is out in the elements it will attract dirt and smudges. These will drastically ruin the quality of the videos you take with them. It is poor practice to be cleaning the lenses when you take them out for use but a quick check is always good. The idea is to keep all your lenses clean after each use before putting them away in their proper place. This will ensure they can stand up to mint condition for every use and last for as long as you need them.