Harry Potter and the Half-Blood Prince filming took place this week in the village of Lacock in the UK. Daniel Radcliffe (Harry Potter) and Michael Gambon (Professor Dumbledore) filmed the scene where their characters visit Slughorn's house in "Budleigh Babberton" and convince him to return to Hogwarts.

The Wilthshire Times has a report on some of the preparation that took place. An excerpt:

They painted a number of houses and put up brown tape on some properties to imitate wooden beams.

Residents in Church Street have been asked to black out their windows with blinds during the nighttime filming.

A giant light was set up behind Cantax House to flood the street in artificial moonlight and crowds gathered to watch what was going on.

A member of the film crew said: "The light will look like moonlight and it is made up of lots of smaller lights inside to give that strong effect.

Meanwhile, Leaky has several reports on the filming. One says:

The part I saw was the walk to, and entry into the house. They did about 6 takes. When I left they were shooting them leaving the house, and you could hear Slughorn's voice agreeing to take the job and demanding a pay rise. Inside the doorway I could see a white staircase and light blue walls.

You can read more from this report and others at this link.

Pictures of the prep are available here and here. Images of the filming, in which you can see Dan and Michael on set, are up at this link.