Ball Compression Contact Patch Marks Showing How Much Balls Compress and Flatten During Impact

Yesterday, I filmed a bunch of power breaks for a video I'm working on. Check out all the contact patches on the balls due to ball compression during impact:

ball-contact-patches.jpg

It is hard to believe the balls compress and flatten enough to make such large marks, but the spots don't lie. Have you guys seen this before and know if it occurs more with certain brands/models or dirty/clean/polished balls? These Aramith balls were cleaned with Aramith Ball Cleaner about a month ago and have had only moderate use.
I have Centennials, Aramith Tournaments, and Cyclops skittle balls, only my Centennials get these marks. I thought it had something to do with the polish I use but then you think that this would happen to the Aramiths and the Cyclops too but it doesn't. I have a Diamond ball polisher and I use the Aramith ball cleaner, not the ball restoring polish though. I think that the ball restore is for use on a rough, neglected set of balls, it has a much more aggressive grit to it. I bought all of mine new and rotate thru them all so no set is really used up. If you find out what causes this I would be more than happy to find out. All of the balls get used on my GCI with Simonis on it, doubt that that matters though.
 
Had that same exact look on a set of balls I cleaned for a tavern we play one of our leagues at. We were the away team a week after I cleaned them, so didn't get back there to shoot till the week following, two weeks later. The balls were horrible looking, weren't good to start out with, but looked pretty good after I cleaned them with Aramith cleaner.
Virtually no spots at home with the same aramith cleaner and Aramith premium, and Aramith Tmt duramith balls. I do occasionally see a spot on the premium balls in the dark color areas.
 
Yesterday, I filmed a bunch of power breaks for a video I'm working on. Check out all the contact patches on the balls due to ball compression during impact:

ball-contact-patches.jpg

It is hard to believe the balls compress and flatten enough to make such large marks, but the spots don't lie. Have you guys seen this before and know if it occurs more with certain brands/models or dirty/clean/polished balls? These Aramith balls were cleaned with Aramith Ball Cleaner about a month ago and have had only moderate use.
So are these balls damaged?
Can they be polished to like new condition?
 
I have Centennials, Aramith Tournaments, and Cyclops skittle balls, only my Centennials get these marks. I thought it had something to do with the polish I use but then you think that this would happen to the Aramiths and the Cyclops too but it doesn't. I have a Diamond ball polisher and I use the Aramith ball cleaner, not the ball restoring polish though. I think that the ball restore is for use on a rough, neglected set of balls, it has a much more aggressive grit to it. I bought all of mine new and rotate thru them all so no set is really used up. If you find out what causes this I would be more than happy to find out. All of the balls get used on my GCI with Simonis on it, doubt that that matters though.
Same for me
 
I have Centennials, Aramith Tournaments, and Cyclops skittle balls, only my Centennials get these marks. I thought it had something to do with the polish I use but then you think that this would happen to the Aramiths and the Cyclops too but it doesn't. I have a Diamond ball polisher and I use the Aramith ball cleaner, not the ball restoring polish though. I think that the ball restore is for use on a rough, neglected set of balls, it has a much more aggressive grit to it. I bought all of mine new and rotate thru them all so no set is really used up. If you find out what causes this I would be more than happy to find out. All of the balls get used on my GCI with Simonis on it, doubt that that matters though.

Likewise my 20 year old Centennials get these but not other balls.
 
If it comes off with the elbow, then the transfer of the white dots could be cue ball powder.
 
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Way back when, players used to comment about balls going dead in long sessions. I dismissed it as a function of ball temperature increase after repeated hammering. The size of those spots seem to point to ball connectivity as well. This could be important research. Aramith Xtra Long etc...
 
If the contact time is linearly proportional to the speed, yes...
Contact time is nearly constant. If the compression force law were Hooke's Law, the contact time would be constant. This is very simple physics.

But the compression force law is closer to Hertz's Law. The "spring constant" is not constant as in Hooke's Law but rather increases with the compression as more of the balls come into contact. Instead of the force being proportional to the length of compression, it is proportional to the 3/2 power of that length. It turns out that for spheres, the contact time decreases with increasing speed but rather slowly (the 1/5 power of the speed).

Here is a fairly easy to understand paper on the subject:

 
Contact time is nearly constant. If the compression force law were Hooke's Law, the contact time would be constant. This is very simple physics.

But the compression force law is closer to Hertz's Law. The "spring constant" is not constant as in Hooke's Law but rather increases with the compression as more of the balls come into contact. Instead of the force being proportional to the length of compression, it is proportional to the 3/2 power of that length. It turns out that for spheres, the contact time decreases with increasing speed but rather slowly (the 1/5 power of the speed).

Here is a fairly easy to understand paper on the subject:

What about packed into a tight formation? I recall something from Billiards Digest saying the rack acts like a solid before it degrades into moving balls.
 
you think perfectly clean balls would still leave the mark? i wouldn't think so but i'm no scientist. i do know they aren't caused by the pockets or chalk.
Perfectly clean balls might still have a factory coating. Pockets I think not. Chalk would definitely abrade an unprotected surface but that wouldn't clean off. I find the perfect circles amazing though. It's a job for CERN.
 
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