Moho Forum

My scene is of a large bird flying in front of the camera. The background consists of a sky, a desert ground and a distant mountain which slowly scales down and appears to descend gradually below the line where the sky and the ground meet.
I placed several props sequentially in the forground to create the illusion of movement. I want the camera to be well above the props as they recede to the vanishing point. To make a prop appear to sink below the horizon I created a second key to vertically scale down the prop until it's almost flat and then disabled visibility at the next frame.

The problem is that the props seem to 'speed up' as they approach the horizon which puzzles me. (I will post a video to YouTube if my description is unclear.)

The farther away an object is, the slower it moves.

From your description I have to guess which kind of perspective you want to build. A picture would've been nice.



On the left I've indicated the kind of movement you'll need (the dots mark the positions of the box). It is not really possible to achieve this with only two keys in AS. Technically it should be possible with a motion graph ... but not in AS.

So on the right you see how equal increments in perspective are constructed. All slanted lines are parallel to each other.

To make things easier when working in perspective, you should use the "origin" trick:


You set the point of origin of the layer with the box to your vanishing point. Now use the scale tool ... it scales and is still placed in exact perspective. Third row shows how to maintain equal increments again.

That's what I needed to know. Your illustrations clarified things for me. I guess I need a Flickr account. Thanks.