2 Replies Latest reply on Feb 5, 2014 5:50 PM by Mike in Ottawa

# Rotating 3D cube with orbit camera and keyframes, on playback it keeps zooming in and out.

Hi folks,

I am a newbie, looking at tutorials and trying things out. I created a 3D object (a Doctor Who TARDIS) just for fun and I'm trying to figure out how to animate it spinning in space with the orbit camera and keyframes. I do the orbit and the keyframing works fine, but when I play it back the whole thing zooms in and out madly, almost like it is throbbing in and out. This funny "throbbing" happens in between the keyframes.

The zoom attribute in the camera options is actually locked, the only attributes changing as I move along the timeline are the position attributes, which I am keyframing off.

I cannot figure out what I've done wrong as I know a nice, gently orbit around the center line of the cube is possible, just not for me!

Any suggestions?

Mike in Ottawa

• ###### 1. Re: Rotating 3D cube with orbit camera and keyframes, on playback it keeps zooming in and out.

Create your box from 3D layers at comp center, add a camera, Add an Orbit Null, rotate the orbit null in Y. This sounds kind of like what you did except that your box is not at comp center or the orbit null is not at the geometric center of your box.

Second, Create your box and put a 3d null at the geometric center of the box. Make the 3D null the parent of all 6 sides of your box. Animate the Y rotation of the null.

The second option has a few advantages. It's easier to create a 3D world to fly your box through and you can easily animate the camera position to push in or pull back from the box.

An easy way to create a box at comp center is to drag all sides of the box to comp center, make all 6 layers 3D layers, press the A key to reveal the anchor point for each layer.

If the vertical sides of the box are all 200 pixels wide and 400 pixels tall then the anchor point for these layers will be 100, 200, 0. To arrange them in a cube set the anchor point for the six sides to 100, 200, 100.  With the anchor point set to 100 in Z you rotate side 1 90º side 2 180º and side 3 270º This will create a box exactly at comp center.

If you have top and bottom layers that are 200 X 200 and the sides are 400 pixels tall then set the anchor point for the top and bottom to  100, 100, 100 and rotate the top layer 90º in X and the bottom layer 180º in x.

Add a new null to the comp, make it 3D and then parent all 6 layers that make up your box to the null, lock the side and top layers, and animate the null...

Here's a project file for you to play with. (CS6)

• ###### 2. Re: Rotating 3D cube with orbit camera and keyframes, on playback it keeps zooming in and out.

Hi Rick,

Brilliant! It works just like I had envisioned!

Thank you very much for your response. There is an awful lot to learn in there and I'm getting there a bit at a time.

Mike in Ottawa