I have read in a couple of places about people using UV filters on the fron of their XM-2 to protect the lens surface. where do i get such things both for the normal lens and for the wide angle adaptor (preferably in the UK) and what effect, if any do these have on my pictures?
I always use a UV filter in front the lens on any of my cameras.
Consider it inexpensive protection for an expensive lens.
They can be purchased at many photo shops, or even over the internet.
The main purpose of the UV filter, is to filter out UV light rays at 400nm.
One of the better UV filters out there is the Hoya Pro 1 UV filter.
It is more expensive than some of the others out there,
but it is constructed better with higher quality componets,
like multi-coated dyed optical glass.
And the transmission curve for this filter shows an almost ideal steep straight falloff in transmission to zero at 400nm.