CATransform3D rotate causes half of image to disappear

Question

I'm using the following code to rotate an image, but half the image (down the y-axis) that has been rotated "out of" the page, disappears. How to fix? heading is in radians.

    CALayer *layer = myUIImageView.layer;
    CATransform3D rotationAndPerspectiveTransform = CATransform3DIdentity;
    rotationAndPerspectiveTransform.m34 = 1.0 / 500;
    rotationAndPerspectiveTransform = CATransform3DRotate(rotationAndPerspectiveTransform, heading, 0.0f, 1.0f, 0.0f);
    layer.transform = rotationAndPerspectiveTransform;

Answer 1

  layer.anchorPoint = CGPointMake(0.0, 0.0);

Answer 2

The solution to this was to set the zPosition property of all my layers appropriately. Thanks is due to @Brad Larson, who suggested this solution in a comment here. It seems that, when you start using CATransform3D, the normal zindex view hierarchy established by addsubview is thrown out the window.