Recordings from the new JVC camera

http://www.youtube.com/watch?v=jej4WNRGyR8

Cool. Though it's hard to imagine dice setters feel much comfort from all the visible twisty turny motions apparent in slow mo.

Yeah, it's QUITE educational for everyone, I think. The truth is that most people fill in the gaps of what they can see with the naked eye with something that is much simpler motion than what is observed in slow motion.

I'm relatively happy with the results of this camera, but I still want the $8,000 camera. This is a $900 camera, and it's the best one that I know of for under $1,000.



But I still want the $8,000 camera.



I may end up getting the $8,000 camera soon.

The difference is resolution. The cheaper consumer cameras are only 640x360 or smaller in resolution.

It's really blurry, but you can see what's happening well enough for research I guess.

Very cool.

But were you trying to thrown them connected / on axis? It appears like you were just flinging them...

I get this question a lot from people who aren't experienced at looking at slow motion dice results. Most people think their shots look great when they aren't looking at them in slow motion. When they look at them in slow motion they are surprised to see such different bounce characteristics than what they had in their mind at regular speed.

That being said these are not my best shots, they are just the shots with the outcomes that I was interested in looking at and had interesting stuff to look at.

I am focusing on looking at any shot that results in the two faces from the top of my set coming up to see if I can find any explanation for why those might come up more often.

I think that you're in a mindset where the bias is more obvious. Any bias that anybody can get is generally going to be pretty tiny (small single digit edges). That's not going to look like a golfer who hits a hole in one on every shot.

OK. I watched it again.

The dice enter the frame way too late to be sure, but, yeah, I do think you set the dice in a hardway pattern and were attempting to keep them together and on axis.

I look forward to seeing it after you get the new camera, showing it even slower with more time devoted to before the first bounce. And with a second camera, a shot with you setting and throwing. I suppose that part could be shot in real-time....


For the record, I've never been one to give much credit to the dice setting / crontrolled shooting theory. But it sure is fun to watch!

That's a great camera. It has amazing resolution and frame rates for that price range. Its 60fps still image capture is incredible.

By the way, if the footage is displayed at 30fps, you can make it even slower motion by running it at 24fps. For the web, you might be able to slow it down to 15fps, with only a slightly discernible "stuttering."

Also, it looks like there is space in the frame to push in (physically or optically -- not digitally) a little, which might reduce the "fuzziness."

I actually do a software slow down in Sony Vegas for the referenced you tube video. I actually max it out. So you're looking at a highly slowed down replay from real-time, although I don't have the factor, it's probably about 1/12th or slower from real time.

The main necessity for recording at faster rates is so that you can make out the pips on the dice, really. When the frame period is too large, and the dice are moving fast, you either need a strobe or a fast shutter speed in order to get clarity enough to see the pips.

In terms of technical necessity, 300fps recording at 640 pixels wide is about all you need to see what's going on.

I still want the $8,000 camera though just because I want it to look pretty too and I'm just the type of person to go full-bore on something and I'm still not happy enough with these blurry results. But the framerate on this camera is 300 fps, which is great.

This camera also does better on light sensitivity compared to the Sony "smooth slow record" features you get for under $400. But I invested about $500 into my LED-track lighting setup to make sure I get enough light.

Quote: Ahigh

I actually do a software slow down in Sony Vegas for the referenced you tube video.

Check to see if Vegas is outputting the footage at 30fps. If it is slowing it down to, say, 24fps and then outputting it at 30fps, there might pull-down artifacts that could exacerbate the "fuzziness."

Generally, NLEs (such as Sony Vegas) aren't as sophisticated in converting video as are dedicated transcoders (such as ffmpeg, mencoder, Compressor, Handbrake, etc.).

Quote:

The main necessity for recording at faster rates is so that you can make out the pips on the dice, really. When the frame period is too large, and the dice are moving fast, you either need a strobe or a fast shutter speed in order to get clarity enough to see the pips.

The pips are certainly discernible with your current settings -- I didn't notice any excessive motion blur. Pushing in would increase the pip visibility.

A general rule of thumb is to keep the shutter speed no slower than one half of the frame rate interval. So, if you are shooting at 300fps, your shutter speed should be no slower than 1/600th. 1/600th of a second should significantly reduce the motion blur in the dice, but you could easily go to 1/1000th or faster if you get some inexpensive, bright lights. Brighter lights would also allow greater depth-of-field (optical sharpness) for a push-in.

Strobes for video are likely unnecessary (and way too complex) for this application.

Quote:

In terms of technical necessity, 300fps recording at 640 pixels wide is about all you need to see what's going on.

That frame rate is probably all that is needed for this purpose, and the "clarity" will increase with a push-in.

By the way, displaying 300fps capture at 15fps is a slo-mo ratio of 1:20.

Quote:

I still want the $8,000 camera though just because I want it to look pretty too and I'm just the type of person to go full-bore on something and I'm still not happy enough with these blurry results.

Of course, only the shooter can make the image pretty -- not the camera. Lighting is important here (as is framing). The set (your table) is already determined.

Quote:

But I invested about $500 into my LED-track lighting setup to make sure I get enough light.

It might be good to try a cheap, quartz shop light (or two), and put it close to the action (4' or 5' away). Zoom in a little, and set the aperture a little higher (say, to f4). Then, dial the shutter to the fastest setting you can get away with at the desired image brightness. White balance.

If there is not enough depth of field, close down the aperture more and move the lights closer (or add lights) or slow down the shutter speed (more motion blur).

Results are what count. That is why crews (and usually players, too) want to see dice that hit that back wall and tumble rather than just fall.

No one has to see the slow motion twists and turns, they can trust that they will be there if it looks like the dice are bouncing all over the place.

Quote: FleaStiff

Results are what count. [snip] No one has to see the slow motion twists and turns, they can trust that they will be there if it looks like the dice are bouncing all over the place.

I think that these videos are are being utilized for development of the throw -- not for proof of dice influencing.

Even further, these shots were intended to demonstrate the technical ability of the JVC camera to capture movements of the dice.

The second sequence has the dice touching each other after initial touchdown.

I don't know of anyone who claims that having the dice come into contact with one another is a good way to get a desirable outcome.

I absolutely included it knowing that the dice touched each other.

I don't think anybody is looking at this as thinking I'm presenting evidence that controlled shooting has been proven.

Just some video from my new JVC GC-PX10 is all.

Quote: tupp

It might be good to try a cheap, quartz shop light (or two), and put it close to the action (4' or 5' away). Zoom in a little, and set the aperture a little higher (say, to f4). Then, dial the shutter to the fastest setting you can get away with at the desired image brightness. White balance.

If there is not enough depth of field, close down the aperture more and move the lights closer (or add lights) or slow down the shutter speed (more motion blur).

quartz lights will raise the temperature of all the materials involved, well past typical casino conditions. It will skew your results, but I don't know if it will do it in a significant way.

My understanding of the prevailing DI techniques is that they attempt to minimize as many variables as possible in an effort to produce more (not all) identical results. Raising the temperature of the felt, foam, rubber and wood with the hot lights, will cause them to behave differently. The heat from the lights will also affect the air temperature and humidity. Again, I don't know that these changes would be signifcant, but they would be changes.

I'm using 5 1300 lumen LED bulbs to light the table. There is almost no heat at all. I went through a lot of trouble to get enough light without the heat just to save on electricity and to prevent from sweating from localized heat.

I had a 1000 watt halogen setup that was the quick way to tell that was not a long term solution for how to light the thing up.

I think LED is absolutely the way to go even though it adds a couple hundred bucks to the setup.

Man, that's nuts when you put them in Slow-Motion...the dice hit the felt and then just basically "explode"
Just fwiw...frome everything I've *heard* about DI...you want the dice to have kind of a "dead cat" bounce after touchdown...so they just come up about 1"-3" off the felt and "graze" the backwall...
But I see you've got a different technique to let them bounce up and hit the flat part above the diamonds...interesting...

Snake Eyes!!!

I don't care if you're influencing them or not, watching them in slow motion is great!

Quote: Ayecarumba

quartz lights will raise the temperature of all the materials involved, well past typical casino conditions. It will skew your results, but I don't know if it will do it in a significant way.

1. Roll the camera, and turn on the quartz lights.
2. Shoot the dice.
3. Turn off the quartz lights, and cut the camera.

Not enough time to heat up anything, and very little electricity used.

[EDIT] If one is really concerned about heating the subject, one can also use Rosco Thermashield (but it is probably unnecessary in this case).

Quote: Ahigh

http://www.youtube.com/watch?v=jej4WNRGyR8

seeing all the twisty motions of the dice when it lands (even b4 it hits the back wall), how can there be dice setters?
seems all random to me???

For most people setting the dice is about as effective at controlling the outcome as snapping your fingers after you throw them.

I think the reasons are not that different either. There's an association with the action and the result.

Most people simply have not looked at how dice bounce in slow motion.

The motions of the dice are based on physics, not randomness. I think Chaotic would be a better description of what you're observing. There's a general magnification of any differences the longer and the more times that the dice bounce.

If the bouncing was random, and not based on physics, it would look quite different.

Even more important about dice setting, if you ASSUME that you can get a bias on the outcome in the range of 1 to 10%, the chance of it negatively affecting your bets is still 50% of the time.

It's not enough to bias the dice; you have to bias the dice in a way that benefits the bets that you are taking.

Most people don't even know how to do the homework necessary to take advantage of dice bias even if they were able to accomplish it. And even if you know how to do it, it's not all that interesting to do!

But your observations about how, let's just say, unpredictably the dice bounce are similar to the observations of many, I think.

If you had a machine to deliver the dice the same way each time we could observe how stable the flight/bounce path remains.

Quote: Ahigh

I think Chaotic would be a better description of what you're observing. There's a general magnification of any differences the longer and the more times that the dice bounce.

I think that this is accurate. It also means that small changes in initial conditions magnify into large changes in results (this is the same reason that long-term weather predictions are pretty worthless)

In other words, even tiny changes in the speed and path of the dice when the leave your hands will have large effects on the final outcome.

Don't get me wrong -- I still think that your setup is awesome, as are your slo-mo videos. And I still set the dice and try to control then when I shoot -- it adds to the fun of the game!

Thanks for the support, Ax.

O-Chaos Okay ah's.

I contacted a university professor at the UNLV trying to find an expert on Chaos theory.

I don't know enough about it myself. And I don't know much about how to leverage that knowledge into my research (since I'm pretty stupid on the topic really).

I imagine I am about 6 months away from that being the biggest thing on my plate, so I'm not in a hurry.

I have lots of other stuff to do for the next 2-3 months.

But if there are any Chaos experts out there who want to add to the discussion, here's your cue!

Recently, some people did a paper about this. I think that they found that, with perfect conditions (ie, not a real craps table) the numbers on the bottom of the set were slightly more likely to come up than any others.