That's what I thought. See earlier posts^^^ but in real time you can see the ball spinning the whole way. And contemplating the action, It doesn't appear the ball would pick up that rotation from glancing off either ball.
Which ball was hit first?
- Thread starter Double-Dave
- Start date
skiergd011013
Well-known member
i did 0.25 speed and used the play pause button to do frame by frame. Too close to call without some real good camera equipment. If a decision had to be made based on what i can see with this method, id say a simultaneous hit, no foul.
This is the first frame after contact.
The 3 is already further away than the five. The 3 took the bigger hit.
The 3 is already further away than the five. The 3 took the bigger hit.
The sound was of two individual contacts.
The direction of OBs was indecisive.
The movement (spin) of CB was indecisive but leading towards bad hit.
The direction of OBs was indecisive.
The movement (spin) of CB was indecisive but leading towards bad hit.
Even with the slow-no video, it would be extremely hard to tell. Although it most likely should be ruled as a simultaneous hit, if I am the TD asked to judge this shot, I might choose to call a foul just because there were likely other options and I didn’t appreciate the shooter putting me on the spot to make this decision, especially if he had other options he could have played.
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In real time the rock followed the 5. Infinitesimal teeter but the ball followed the 5 therefore 3 first.
I agree the 3 rolls faster then the 5 does, but does that mean it was hit first or second? If the 5 was hit first that was near-as-makes-no-difference a half ball hit, the tangent line would then take the cueball towards the 3 with a full ball hit on the 3, right?
You would call a foul simply because you were asked to make the call, not because you actually think it was a foul? That makes no sense whatsoever.
Yes, possibly, if it was too close to call and if he/she was a good enough player that they had other options they could have chosen to avoid forcing me having to make a tough call.
No. The line towards the second object ball is also half-ball by the 90-degree rule. This means usually the ball struck first in a symmetrical situation will have more speed and the cue ball will come off away from that faster ball. The cue ball has to move away from that faster ball to satisfy conservation of momentum. If you have the normal A and then B hit in that situation, the second ball will be moving only half as fast as the first ball.
If you record five more such shots with a perfectly symmetrical set up, I think all of them will have much more speed on the cue ball. I think in five tries you will not achieve what I think was a "partially simultaneous" hit on the object balls in your video.
I think it's unfair to penalize the player for making the ref's job harder. Maybe there was a pocket along the line the 3 went and it was the only way to continue the run.
In our room for our tournaments, at least among the better players, it seems to be a matter of etiquette that if it looks like it’s going to be a really close hit, they won’t play it and they’ll find another shot to play. As the TD and the person that would have to judge the shot, I appreciate that. To help me make the proper call, I will take the time to take an overhead slow-motion video of the contact on my phone, before making a ruling.
Again, thank you Bob, I value you opinion highly.
If I understand your responses correctly you still feel the shot is too close to call but if you HAD to chose between the 3 and 5 being hit first you'd chose the 3? Since the 3 has more momentum and the cueball is going left.
There was no pocket, you can just about see the corner pocket and the head string in the video. I could have gone rail first around the 10 but since I felt I could hit the 3 directly and leave it at least difficult for my opponent (there was another ball near the long rail that the 3 would have went behind) that is the route I chose.
Yes, but it is real close, and if the situation is slightly asymmetrical it's hard to figure out what the small speed on the cue ball means.
If the cue ball has a clean A and then B contact on a pair of balls in the symmetrical situation, it will leave the second one at a quarter of it's initial speed (and then curve forward some if it has follow).
Too close to call. For those interested, many more examples, along with explanations for how to determine which ball was hit first, can be found here: