I have, among other digis, a Panasonic Lumix FZ30. I have taken thousands of
pics with it, both in studio conditions and in the street. It has, to say
the least, been well used. In places the silver is wearing off through
constant use and the black is showing through. None of this affects picture
quality of course. Unfortunately however, it has now started to accumulate
dust under the lens. In good light one can see this dust quite clearly. So
far it does not seem to lead to artefacts in the  photo, something which
internal dust did do on an Olympus that I had.

So a question. How can I clean the lens of this dust? I see that looking at
the camera from below there is a small "hatch" at the base of the lens
carrier where it joins the body of the camer. This is secured with a single
screw and looks promising as a possible access point. Or, secondly, I have
found three equi-spaced holes under the rubber ring that rotates for the
manual focus. There are no screws in view, but at a certain point of
rotation these holes line up with three other holes in the lens carrier
body. Do they serve in some way to remove the lens cover/carrier?

Any clues, tips, tricks etc would be very welcome.

Bill