Hi everyone. I uses my RX100 M3 occasionally during overseas trips. Before using it, the front of the lens element was very clean under bright light sources (I've cleaned it with lens cleaner after my last usage months ago).
However, after 1 day of usage during tours. I've noticed that there are some slight markings on the front of the lens element under bright light sources. Especially if you view it against bright light sources on certain angles. I am very careful with my camera and do not let anyone else handle it. How did those marks make their way on the lens element when I have not touch it with my fingers? Under normal lighting, I could not see those markings at all.
If I were to use the camera indoors at my home, I can use it many times without any smearing on the lens element. So I believe that it was caused by air and vapor outdoors that are not visible to humans.
So the question is should I clean the front of the lens element with wet lens cleaner every time after using it outdoors because there will definitely be some markings on front lens element after every single use. Or clean it when there are some serious finger print smudges? Will leaving those slight markings on the lens element harm/eat away or causes fungus on the lens coating? I would like to avoid doing too much cleaning on the lens. Thanks.