Here are some examples:
Here is a small piece about Errol Morris' Thin Blue Line, (1988). This is a fascinating story and very successful as a film. There are a number of formal interviews used in the film- this piece below has clips from the film, as well as a number of filmmakers commenting on it.. each of them framed in various shot compositions. Some are closeup and filling half the frame, others are way in the corner, and balanced by a light source. LOOK ESPECIALLY AT WHERE THEY ARE LOOKING-- they are looking at a position near the camera's lens.
this is about a documentary called the Thin Blue Line
A professional cameraman Simon Wyndham gives tips on framing for interviews: "1. Try to vary your interview composition. In 16:9 don't be afraid to go in closer and crop the head of the interview subject. It is part and parcel of using that frame shape. Try slight angles. You don't have to perform a full dutch tilt, but sometimes a subtle angle can make a dull looking shot look a bit more dynamic. Try having your interview subject standing somewhere instead of sitting down..... more
