Stroboscopic Photography


Stroboscopic photography is a rather more abstract branch of photography, consisting of a flashing strobe light and a camera with an open shutter. Stroboscopic photos must be taken in darkness so that everytime the strobe flashes, a still image is taken of a moving object at that instant.

On the right, a friend is captured on camera while moving her arms down with Penguinslab's newly modified strobe light. The strobe light was simply one bought from an electronics store, but I had to personally modify it internally to increase the maximum flash rate to ~20Hz (originally 10Hz).

Here, a ball's trajectory is clearly seen after being fired from a stationary position. The gaps between each image of the ball is about the same, suggesting a constant speed.

An exposure of a few seconds constitutes many flashes of the strobe, and hence movement of the object can be recorded through a series of images. The flash rate of the strobe determines the time between captures of an image, and can be adjusted according to the speed of the object to be captured.

The strobe light is not bright enough when the flash rate is high, as is in the photo to the right. I had to increase brightness on this photo using software.

It doesn't take a pro soccer player to see that the ball is quite flat, in fact very flat. The fact that the images of the ball are more bunched up at the top of each parabolic bounce is evidence of a decrease in speed, which should be fairly obvious...

Very self explanatory photo here... a hammer striking a nail. Although it does look like I almost missed it... remember this was in complete darkness with the only source of light being the strobe light itself, whose flashes can be very intense. I usually wear dark glasses while taking these photos.

Depending on who you are, and how you interpret images, this photo to the right could look like a syringe or a balloon taking off or all sorts of things (according to comments I have received about this). It is, in fact, none of those things. This is the same hammer as the picture above, but this time levering the nail out of the wood using the other side.

The nail is visible clinging to the end of the levering arm in each capture.

Stroboscopic photography can also be used for high speed purposes, like taking pictures of the bullet from the coilgun, for instance. This bullet was actually ejected at a very low speed, because if the power to the coilgun was turned any higher, the strobe light could not flash fast enough to capture anything. A higher speed stroboscopic photo of the bullet can be found on the coilgun page.

Similarly, here is a photo of the trebuchet in action. The angle at which the counterweight swings up to can be observed, and the maximum deviation of the throwing arm can be seen likewise.

Unfortunately, the strobe light was not bright enough to be able to illuminate the pouch and projectile at all, so that portion was cut off.

Back to the hammer! It is not that hard to see that this is simply a hammer hitting a golf ball off a plank of wood.
Hmmm... my fingers are taking a stroll. I admit this photo can be confusing if you have no idea of the context!

What is going on here?


A plastic ruler is originally placed leaning against a wall (the brightest white stripe). I go to grab it (see the hands going towards it from the right?) and the ruler can be seen moving, and immediately after that I grasp the ruler tightly and take it away.





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