4/3 adapter & 2x converter
 

I'm trialing 2 GH1's for shooting weddings but would like to get closer than the 140mm zoom - I got the 200mm but I'm wondering about getting the micro 4/3 to 4/3 adapter and using an olympus lens with the 2x converter.

anyone tried anything like this?

Remember that with the 2 to 1 crop factor, your 140mm is more like a 280mm lens.

GH-1 + 200mm
 

I have the GH1 and the Canon FD 200 f2.8. As the other poster mentioned, 2x crop factor is like shooting a 400mm lens.

My thinking is you'll need a tripod, and that may be a not practical for a wedding.

By the way, while I like it overall, my biggest gripe is the dearth of bright m4/3 "native" lenses across the spectrum, Panny's 20mm f1.7 excepted. In low light like weddings, you may find this to be a problem.

Every teleconvertor or lens adaptor I've ever used on an SLR has had some kind of warning that says something like: "Do not use this lens converter with any other converter." Although that could be absolute rubbish designed to scare people into buying "native" lenses for their camera and generating more profit.

Your 200mm lens will give you an equivelant of 400mm which is about the same as an average consumer camcorder with a 10x zoom lens at full telephoto. That should be plenty for Weddings.