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Contrasting the example above, here you can see in action the problem I am talking about:
http://www.eli0s.com/parallax/index.html
The starting position of the player is on the top-left of the layout and his shadow/bulletholes are being generated in a layer below, with lower parallax values (90,90). At the beginning, everything seems to work ok, the shadow is in place and the bulletholes appear at the mouse.X, mouse.Y. The further you stray away from the starting point though, the more you can observe the offset I am talking about. You can download the capx file here if you like:
http://www.eli0s.com/parallax/ParallaxExample.capx
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eli0s
Why are you wanting the shadow/bulletholes to have lower parallax rate than your player?
parallax would start out being fine because little variation in layers' position but parallax is meant to create that offset that you are saying is error
That's my take on parallax anyways