Cal Club Autocross Forums

How can half of that front tire be blurred and the inside half be sharp? I've taken untold thousands of racing photos ... never seen that before.

1/250th of a second ... NOT PHOTOSHOPPED ... except to crop, density correct, etc.

1. Secret new Kumho two piece tire that allows the inner and outer sections to rotate at different speeds.
2. Intentionally blurred to to prevent you from seeing a secret new tread pattern.
3. Outer half of tire is simply worn. That's what it looks like when I zoom in on my 32" work monitor, not blurry, just worn.

my guess is that it is due to the direction of the voids. the clear set is turning (in relation to the viewer) longitudinally, so the edges that would create the blur (since they define the shape you are looking at) aren't moving at the same rate of speed as the blurry set, which have edges turning perpendicularly to the viewer, and therefore moving at a higher relative rate of speed.

Said another way, given the perspective of the viewer, individual components of the tire are actually moving at different rates of speed.

To illustrate better, imagine you took a set of 710s and created new grooves running from sidewall to sidewall and then took a picture of it at speed heading straight towards you. The vertical grooves would still be easy to see, but the horizontal ones not so much.

I wonder how this all fits in with einstein's theory of how relative time changes with changes in speed.

Rick Brown wrote:1. Secret new Kumho two piece tire that allows the inner and outer sections to rotate at different speeds.

The funny part (at least to me) is that this is actually true! See my post above.

KJ Christopher wrote:my guess is that it is due to the direction of the voids. the clear set is turning (in relation to the viewer) longitudinally, so the edges that would create the blur (since they define the shape you are looking at) aren't moving at the same rate of speed as the blurry set, which have edges turning perpendicularly to the viewer, and therefore moving at a higher relative rate of speed.

Said another way, given the perspective of the viewer, individual components of the tire are actually moving at different rates of speed.

To illustrate better, imagine you took a set of 710s and created new grooves running from sidewall to sidewall and then took a picture of it at speed heading straight towards you. The vertical grooves would still be easy to see, but the horizontal ones not so much.

I wonder how this all fits in with einstein's theory of how relative time changes with changes in speed.

Waaay to deep for a Friday afternoon......

I think KJ's close. The (viewer perspectice) right side is blurred along the groove while the intersecting left side is blurred against them.

We can rule out relative camera movement, because the body is not blurred. For the same reason, it cannot be subject movement across the frame.

I think that the steering angle was being changed (i.e. the driver was moving the steering wheel to the right, tightening up the turn) during the exposure, making the relative motion *along* the inside tread angle but at an against the angle of outside tread. To better visualize it, if you'd put a bright white dot on the inside (toward's the center of the car, not the turn) tread, you'd see a blur roughly lined up with the tread pattern but a dot placed on the outside tread would be blurred at an angle against that side's tread. Both blurs would have the same orientation relative to each other.

Fun puzzle!

Damn you, Mako, don't *make* me geek out....

Will Kalman wrote: The (viewer perspectice) right side is blurred along the groove while the intersecting left side is blurred against them.

Exactly. The individual components of the tread are all traveling a the same rate. However, the object being focused on is the void, and those are moving differently. The left side is moving in a perpendicular relationship to the void, so you see the movement as a downward movement, traveling at the same (or near) the speed of the tire. Like if "_____" were moving downward, you would see movement easily. The right side is traveling more with direction of the void, so if you were to focus on an area, the movement would be more horizontal and the void you are following with your lens is traveling a much shorter distance (from left to right, rather than top to bottom) in the same time and thus appears slower.

Or, think of a barbershop pole spinning around. If you have it in a vertical orientation and stare at one spot, the lines would appear to be moving up or down, through the spot you are looking at. If you move the orientation to say 45* from vertical and continue to look at the same spot, there would be a much slower appearance of movement in the lines, and if you orientied it at just the right angle, the lines would appear to stand still.

Hey....where can Iget colorful arrows for my tires?

Will Kalman wrote:Damn you, Mako, don't *make* me geek out....

I think the steering motion has an impact on the visualization, but I don't think the visualization is dependent on the steering motion. You can get the same results with my custom grooved 710 example above with zero steering movement.

In addition to the differen angles and therefore relative speed of the groves as mentioned above, it looks like maybe a camera sensor/firmware issue to me that was triggered by the speed and pattern.
I have seen all sorts of strange things that people have been bitching about on the digital camera forums, and sometimes have seen some of these things show up in my pictures too.
What camera model and do you have a hig-res crop of the tire?

KJ Christopher wrote:I think the steering motion has an impact on the visualization, but I don't think the visualization is dependent on the steering motion. You can get the same results with my custom grooved 710 example above with zero steering movement.

Yes, but the real question is the difference between the left and right sides in Mako's photo. My explanation says that active steering is causing that difference in Mako's photo by changing the movement vector from directly circumferential (as in your example) to one at an angle - the angle of the tread pattern.

Yes, but the real question is the difference between the left and right sides in Mako's photo. My explanation says that active steering is causing that difference in Mako's photo by changing the movement vector from directly circumferential (as in your example) to one at an angle - the angle of the tread pattern.

Oh, there is no question that active steering will have an impact. I completely agree. But I don't think that it is as necessary in a still photo as it would be in a moving picture. In fact, if it had a major impact, I would expect to see less crispness in the portion of the photo showing the edge of the wheel towards the rear of the car. If there were enough steering impact during this 1/250th of a second to create that much differential in the two sides of the tread, I just don't think the edge of the wheel would be as clean as it is.

Kurt's son (Max) should use this as his physics experiment.

Personally, I think the outside of the right front wheel has moved through a small black hole and what we are seeing is a time space distortion. This small black hole was generated by tiny alien life forms based on generating energy from arsenic (instead of photosynthesis). Their little scout spacecraft was materializing on the pavement just as the Miata's wheel and tire crushed it into oblivion. Their invasion fleet is behind Mars waiting to hear back from the scout ship before attacking.

OT but that tire looks like the new TOYO!!!



see???



So close!!!

Photo of Jeff R. driving was taken as he came off the finish chute, ie. couldn't have been going more then 5 ? mph?

1/250th second in case you missed that.

Photochop! Wouldn't be the first time...

? too much work, for me anyway ... for a "joke"

Swamp gas reflected by a weather balloon. ... The truth is out there.

vasoline on the lense left over from high school photo class project

btw this is the most face time i have gotten in years

what are the little orange spots on the wheel. i dont think the yellow stickers on the car reflected. seems like an exposure issue to me

i dont think there is a physical reason for the blur on only part of the tire. pretty strange


i like this photo of the bushes coming off the wheels in motion lol

http://public.fotki.com/makofoto/2009-a ... g1124.html" onclick="window.open(this.href);return false;

He is an alien and those tires are made of a material not known to man.

Jeff Ringer wrote:what are the little orange spots on the wheel. i dont think the yellow stickers on the car reflected. seems like an exposure issue to me

Cone reflection.

Mako Koiwai wrote:Photo of Jeff R. driving was taken as he came off the finish chute, ie. couldn't have been going more then 5 ? mph?

1/250th second in case you missed that.

1/250th isn't all that fast, even at 5mph, the tread will move about 0.35 inches in that time. Easily enough to blur those tread blocks.

KJ: Yeah, looking at the trailing edge of the rim, I'd expect to see some blur but I I'm not sure I do or not. Without the front edge of the rim to compare to, it's hard to say whether that rear flange is blurred or just overexposed. The top and bottom of the rim wouldn't be affected by *either* motion and the hub section not so much either, so they're no help.

I also notice that you can see the sidewall printing on the top but lots of blur at the bottom. That could be a shadow/exposure issue, too.

"CSI:Fontana"

darker ...