DDP - Setup p2
Find a table with about 6 feet of clear space past the end. Set a chair on the top of the table to act as the support of the top of the ramp.
Tape the top of the half-pipe to the chair prop. It is easier to get a good track curve if the track starts horizontal. Note that chair is set up on top of table, this provides a better and less error-sensitive trajectory for catching the marble later.
Extend cup 'base' away from table prop, far enough so that no part of the track is vertical, but close enough that the track touches the ground before rising up to the level of the cup. The nadir of the marble's run should barely touch the ground, to give the maximum launch distance after it departs the ramp.
Here's an example of a ramp that is far too steep. You can see in the picture that the ramp is actually more than vertical! It extends backwards for a brief stretch. Make sure your ramp doesn't do this, as the marble will skitter on its way down, making the calibration very difficult.
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