If you apply a Spiral In animation to an object in PowerPoint, you may find that the spiral is somewhat wider or narrower in the published presentation than it appears in PowerPoint.
This is a known issue. You may be able to work around it by applying a spiral Motion Path:
- In PowerPoint, select the object.
- Click the Add Effect button in the Custom Animation pane.
- Scroll to Motion Paths, and select More Motion Paths.
- Select Spiral Right or Spiral Left.
- Resize the animation to the desired scale.
- Publish your presentation.