Spotted these two on the branch of my orchid plant, getting down to business! In fact, this particular plant seems to be quite the love-spot for these flies - I've spotted such incidents on numerous occasions.
At first my Panasonic Lumix DMC-F2 had real problems focusing on the flies. It persisted on focusing on the background. The only clear picture I could get was too far away from the flies to see them!
So I grabbed a piece of white paper and with one hand held it behind the flies whilst I focused the camera in the other hand -and hey hey, it locked on to them beautifully! This is a decent little tip if you're having focus problems with small objects. Neutralize the background with a piece of white paper!