This series is dedicated in understanding slider movements.   Create 10 identical clips and arrange them one after the other along an imaginary z axis.  Create a camera object and compute its position throught the slider.This version explores the movement of 3D cameras along the Z axis. 

This code is heviluy based on the 3D flythrough post  and the equation bellow moves each element's Z position to synch with the camera's z value, this creates the illusion of a traveling camera in 3D.  Now I know the Fiash has no _z property, but there is no reason why we cant create on in order to acheive our goal. Interact with slider to see it in action.

	// camera z position
	this._z =  centerZ - dir*(this._parent.oCamera.dz - this.z) * distance;

	// Calculating actual scale values according to scale = dz/(z+dz) formula
	var scale = focalLength/(focalLength+this._z);

	// set size
	this._xscale = this._yscale = scale*100;