Thanks! With the information in the article you just linked, I am now very suspicious that this is a picture of the bullet, where I previously thought it was plausible from my low-precision estimate. From the article:
“If the gunman was firing an AR-15-style rifle, the .223-caliber or 5.56-millimeter bullets they use travel at roughly 3,200 feet per second when they leave the weapon’s muzzle,’’ Mr. Harrigan said. “And with a 1/8,000th of a second shutter speed, this would allow the bullet to travel approximately four-tenths of a foot while the shutter is open.”
Same procedure, but an AR-15 shoots a bullet faster than the speed for a generic bullet that I used, and the shutter speed was faster because it was a fancy NYT camera. 3200ft/s is almost exactly 1000m/s. The 1/8000s shutter speed is the fact that seems the most reliable, assuming that the photographer knew what setting their camera was on.
What I disagree with is that that streak is only 0.4 feet long. The average size of a human male head (brow to back of head) is about 20cm, or 8in per this image from Wikipedia. The streak from the bullet in the image is about twice the size of Trump’s head, or 40cm/16in. Due to projection effects, this is a lower bound on the path of the bullet during the 1/8000s exposure. This puts a lower bound on the speed of 3200m/s. This is over three times the velocity of an AR-15, at minimum. Either this was some super-high-powered rifle to fire the bullet that fast, the shutter speed is misquoted (or a misleading representation of the exposure time), or this isn’t picture of the bullet.
Thanks for providing the data to make me suspicious that this is an image of the bullet.
assuming that the photographer knew what setting their camera was on
The photographer would definitely know even if the camera was in a mode that selects the shutter speed automatically because it’s embedded in the image file’s metadata, which is shown in software used for image processing.
Note publishing and social media platforms usually strip metadata from images.
What also doesn’t make sense is, if you roughly line up his arm position in the three NYT stills vs going frame by frame in the video/audio playback captured by the various news outlets, he raises his hand to his ear nearly 2/3rds a second after the audio recorded first shot, which, given bullet velocity and distance traveled was probably nearly a full second after the first shot (so a super slow reaction time, which normal nervous system reaction time is .150-.300/sec), since you’ll hear (and audio record) the shot roughly 5 frames after it’s passed by. He starts to lift his hand off the podium at nearly the same time the second shot estimates to be fired, and maybe 3-4 frames before the first posted NYT pic catches the bullet supposedly whizzing by.
Thanks! With the information in the article you just linked, I am now very suspicious that this is a picture of the bullet, where I previously thought it was plausible from my low-precision estimate. From the article:
Same procedure, but an AR-15 shoots a bullet faster than the speed for a generic bullet that I used, and the shutter speed was faster because it was a fancy NYT camera. 3200ft/s is almost exactly 1000m/s. The 1/8000s shutter speed is the fact that seems the most reliable, assuming that the photographer knew what setting their camera was on.
What I disagree with is that that streak is only 0.4 feet long. The average size of a human male head (brow to back of head) is about 20cm, or 8in per this image from Wikipedia. The streak from the bullet in the image is about twice the size of Trump’s head, or 40cm/16in. Due to projection effects, this is a lower bound on the path of the bullet during the 1/8000s exposure. This puts a lower bound on the speed of 3200m/s. This is over three times the velocity of an AR-15, at minimum. Either this was some super-high-powered rifle to fire the bullet that fast, the shutter speed is misquoted (or a misleading representation of the exposure time), or this isn’t picture of the bullet.
Thanks for providing the data to make me suspicious that this is an image of the bullet.
The photographer would definitely know even if the camera was in a mode that selects the shutter speed automatically because it’s embedded in the image file’s metadata, which is shown in software used for image processing.
Note publishing and social media platforms usually strip metadata from images.
3200ft/s is muzzle velocity, that’s going to drop over the distance.
Plus the velocity depends on how hot the load is. An AR-15 can be as high as 3,200, but it can alao be lower.
https://www.spartanarmorsystems.com/understanding-bullet-speed-how-distance-affects-armor
Right, all more reasons the streak in the image is too fast to be an AR bullet.
What also doesn’t make sense is, if you roughly line up his arm position in the three NYT stills vs going frame by frame in the video/audio playback captured by the various news outlets, he raises his hand to his ear nearly 2/3rds a second after the audio recorded first shot, which, given bullet velocity and distance traveled was probably nearly a full second after the first shot (so a super slow reaction time, which normal nervous system reaction time is .150-.300/sec), since you’ll hear (and audio record) the shot roughly 5 frames after it’s passed by. He starts to lift his hand off the podium at nearly the same time the second shot estimates to be fired, and maybe 3-4 frames before the first posted NYT pic catches the bullet supposedly whizzing by.
Very true, but it was only 300".