User:Labrat/Sandbox

The following axis tilt & rotation overlay is provided by permission of Bill Sempsrott from blueprintbowling.com. It is mathematically correct and is based on a point of view level with the centre of the ball and an infinite distance away. The existing wiki overlay is provided for comparison - the overlay lines approximately correct for a viewer two feet from the ball. For video work from the back of the approach at the height of the centre of the ball, the Blueprint version is correct with a perspective error of less the 0.5%. The difference between the two overlays is discussed in this Blueprint article: http://blueprintbowling.com/blog/Posts/axis-rotation-and-axis-tilt-explained.aspx

File:Axis-rotation-axis-tilt-overlays.jpg