disney trickery?

[mr. piper]

after seeing the Q. from CHILLUM, entitled"BIG MOON RISING". I was reminded of a short film i once saw with Walt Disney himself describing a technique his animators used to compensate for the aparent size of the moon/sun in the sky of an animation set. This involved adjusting for the anomalie(?) of the moon getting larger as the camera moved towards it, as in following a character moving away from the initial foreground and the scenery coming closer as the camera advances. as the scene gets bigger the moon would if it was part of the set also appear larger, the reality is that any object that is advanced upon does seem to take up more of the scene, except for the sun/moon/stars etc. that are so distant that the increase in size is indescernable.

 Disneys method involved the scenery being made of layers, foreground background etc. at 90� to the focal plane that could be spaced at differing intervals, so that the last layer could always be the same distance from the camera even if the camera advanced, thus the moon would appear to stay the same size. I think that is how it went, and i hope you can fathom my babble. but i would like to know more about it as i intend to do some 16mm animation when i am able.

[landie]

Yes, it's entirely different for animated films as they have a false horizon or dissappearing point. The real life images of Sun or Moon, where the image is disproportionately large is achieved using (long) or telephoto lenses to magnify the subject matter, hence the shallow depth of field.

[jake-the-peg]

Disney's animations were built (as most are) on a number of layers of transparent film. If you 'zoomed' in on a scene by moving the camera closer during a number of exposures, then the object would get larger in the field of view. However if the moon (for example) is on the bottom transparency then it will get larger too which is the same effect that we're used to seeing in a zoom lens zooming in on a scene.

I'd imagine that in Disney's time zoom lenses had not been invented or were very rare and audiences found the effect jarring.

By making a physical connection between the camera and the bottom transparency as you 'zoom in' the bottom transparancy is moved back and you get an effect whereby the moon is always at the same distance from the camera as the it approaces the  top layers of film. This gives an effect whereby the moon remains the same size whilst the object increases in the field of view in the same way as if a cameraman physically approaces the subject.

Obviously you need to keep the whole cell in focus so if there is a big gap between the top and bottom transparency the aperture needs to bet set small enough and you need plenty of light.