4th of July in small town NM

[reneethomas]

I will post more later but I have a question on this picture:



What would cause those coffee pot looking things. I did not notice them until I got home and downloaded the images.

[jubu]

Maybe that was the actual trajectory of the fireworks and the slow shutter captured it?

[NeutronBoy]

seems to me like the camera got moved or bumped and you are seeeing the path it took. I think that's the case because they all look nearly identical and are occuring at about the same time judging by the position on each streak.

[reneethomas]

Originally Posted by NeutronBoy

seems to me like the camera got moved or bumped and you are seeeing the path it took. I think that's the case because they all look nearly identical and are occuring at about the same time judging by the position on each streak.

I don't see how that could of happened. I used a tripod and remote trigger. I am not sure how nearly identical would lead to this theory. I would think had I bumped the camera it would be irregular not regular. Also there is no blurring that would be associated with a bump. Could it be this firework produced this design intentionally somehow? I don't have much experience with fireworks or long shutter so if you could explain this more to me I would appreciate it. I just assumed bump would equal blur but I would be interested to learn more if this is an incorrect assumption. Thanks so much!

[NeutronBoy]

dont forget that the image is created with point sources (burning pieces of the firework) and is not static like a landscape. The camera is 'seeing' the burning debris and recording the trajectory. Think of a bulb exposure tracing a flashlight - you will see the light move along the path of motion and it wont be blurred. same thing if the camera gets moved. A lot of things could cause the shake.

It's unlikely that the firework design would cause the patterns - they are nearly identical. Fireworks are built by hand and are therefore will create similar, but not identical patterns. These patterns are essentially identical to each other.

Another clue is that the patterns for the debris going away from the camera are the same as those travelling toward the camera - there is no change in perspective of the path the debris follows. Definitely camera motion.

[ShakenBlake]

NeutronBoy is right. The identical pattern is what gives it away. Somehow the tripod got bumped or the surface the tripod was sitting on vibrated. What was the tripod on?
Think of it this way, when the camera was bumped, it and the censor moved in the coffee pot shape you see and thus created the squiggles. It technically is a blur but since most of it is black and those were the only points of light the censor was "seeing" at that moment of the exposure that's the only part of the picture that looks blurred. Although it's intentional, the whole photo is actually blurred. Part of it because your subjects are moving plus a split second where the camera moved.

Try doing some tests. In a dark room set up some candles or xmas lights or something with multiple light sources. Take a long exposure and intentionally tap your tripod. All of the light sources should have the same squiggle shape. You might have more of the blur you're expecting in this scenario if a tabletop of other objects end up being lit by the light sources. Do you understand? I can try explaining it differently if needed.

As for the design being produced intentionally by the fireworks people, I would say it would be near impossible. If they had that capability they would use it all the time to make stars or happy faces or something people would ooh and aah about.

[Chris]

Well you certainly got a one of a kind shot.

[viktor061]

shockwave from the blast caused the camera to vibrate