Aiming

[Colin Colenso]

Sure seems that is was well worth the purchase. I would have never thought about getting a truer picture of what is happening.

If you have a moment sometime. Take the same shot and compare the following

1. top english (any english causing the CB to roll forward)
2. OE
3. IE
4. Draw (make sure ball is still spinning at contact)
5. No CB rotation at contact

Would really like to get a sample of the results.

(Edit) Also would be nice to pick medium and fuller (not straight) contacts. In other words have 2 different cut shot angles. There should be a difference here also.

Pete,
There's already quite a bit of theoreticall stuff done on this (you may have seen before) done by Dr. Dave at http://www.engr.colostate.edu/~dga/pool/technical_proofs/new/TP_A-14.pdf

I will conduct a bit of testing using the spider as a guide. It takes a little practice and some accounting for squirt which it seems I can adjust for pretty well using BHE with my established pivot point bridge length.

I'll let you know the results. I'll be in my new apartment with new table in about 1 week so I can conduct some experiments. Also, I can begin shooting some videos hopefully to demostrate some whacky stuff

 

[Colin Colenso]

Colin
Your absolutely right. Notice that no where in my above post does it say anything about a ghost ball. The only thing I mention is that a certain spot on the cue ball and a certain spot on the object ball need to make contact to pocket the ball. Systems like the ghost ball are also just starting points to learn where the actual contact points are.

As you shoot shot after shot after shot you learn that unless a shot is hit rather firm you need to adjust the contact point for throw. The softer the shot the more you need to adjust for throw. Then you have the severity of the cut. The more of a cut the shot is the less throw effect. So high angle cuts like 75 or 80 degrees can be hit softly without making much adjustment for throw.

Then you start adding follow, draw or english and that effects the throw. All this adjusting is why I think a lot of the better players say they aim by feel. There are just so few shots that they aren't adjusting for something. Whether it be speed, amount of cut, or spin, it just seems like there is always something to adjust for. There is no line that goes toward the pocket that goes through the object ball and points to this contact point when your making an adjustment. So we call it feel.

Hi JR,
Yes I know you didn't mention the ghost ball, just the contact points. I brought it up because with the Spider www.thespideronline.com it shows the ghost ball with a laser, and so you can aim at the center of this as an accurate way to connect the contact points.

Here's a graphic produced by tests from Bob Jewett on what you were talking about regarding throw at various angles. His graph also shows the variation with speed.

 

[jsp]

Cool! This graph looks very similar to the drain current versus drain-source voltage of a MOS transistor for different gate-source voltages! Well, almost...if it weren't for the negative slopes of the flat regions. Sorry, i'm in work mode right now.