Hanging miniature is an in-camera

In-camera effect

An in-camera effect is any special effect in a video or movie that is created solely by using techniques in and on the camera and/or its parts. The in-camera effect is defined by the fact that the effect exists on the original camera negative or video recording before it is sent to a lab or modified...

 special effect

Special effect

The illusions used in the film, television, theatre, or entertainment industries to simulate the imagined events in a story are traditionally called special effects ....

 similar to a matte shot

Matte (filmmaking)

Mattes are used in photography and special effects filmmaking to combine two or more image elements into a single, final image. Usually, mattes are used to combine a foreground image with a background image . In this case, the matte is the background painting...

 where a model, rather than a painting, is placed in foreground and the action takes place in the background. It is thus a specific form of forced perspective

Forced perspective

Forced perspective is a technique that employs optical illusion to make an object appear farther away, closer, larger or smaller than it actually is. It is used primarily in photography, filmmaking and architecture...

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Description

There are hundreds of instances where a hanging miniature has been used. They are a very old device and when produced correctly they are almost completely undetectable. Take a look at the 1925 version of Ben Hur for example. Only a very close examination of the chariot race will reveal that above the wall surrounding the stadium and the first rows of bleachers, there hangs a miniature with moving 'puppet' people that can rise and fall with the human extras. Another cost saving effect was that of 'flopping' the negative so that only one side of the stadium miniature was built. The main reason for using a miniature in this way is that, unlike a painting, the light on the built set will always be the same as that on the miniature making it possible to shoot in a variety of different 'lights' during the day.