Hello,
Maybe this has been discussed already, but I didn't get good results from the search engine.
I often ask myself what might be the best way to clean lenses and ports.
For the lens it seems to be quite simple, specially because I use a UV(0) Filter as a protection. So I use lens cleaner and that paper/tissues, or just a soft brush and micro fibre cloth.
What kind of lens cleaner is the best and which chemical (e.g. Aceton) will eventually damage the coating. Maybe some chemicals will damage O-ring, glue or sealant of the ports.
For me, cleaning the inside of the ports is the most hated job. I always try hard to keep them clean as long as possible. The dust can be blown away by air, but any time everthing is assembled, I find "something" on the lens or on the inside of the port. The worst job ever is to clean my 24 cm Superdome.
Who knows the perfect technique and shows the secrets?
Are am I too nitpicking? Normally, a bit of dust particles so close to the lens does not affect the image quality, taking into account the millions of small disturbing things in the water.
Thilo