"I SPY WITH MY LITTLE EYE ..."

Special Programm (6 years +)

Saturday, June the 7th, 11 am, 3001

The bursting of a balloon, the shattering of a glass, the acrobatic manoeuvres of a bird- everything happens in the blink of an eye. But what exactly happened?

Those things take place so quickly that they are hard to spot with the unaided eye. Human beings can distinguish about 60 frames a second, while the common housefly can distinguish about 250 frames. So while a human being barely sees what is going on when she makes a balloon burst, a housefly is able to actually “watch” the balloon burst, since it is perceiving the events at a much smaller pace. How is this possible?

We can compare an eye with a camera capable of recording 60 to 65 frames per second. The compound eye of a housefly can shoot about 190 more frames per second, adding up to approximately 250 frames a second. Since it can record more frames, it sees the balloon bursting in a more precise and detailed fashion. But there is a way for us human beings to see fast things as precisely as a fly – and even more so! With the aid of a so-called high-speed camera we can watch things in slow motion. While regular cameras are recording 24 frames a second, which suffices at fooling a human eye, high speed cameras can record up to 140.000 frames per second. High-end CCD-cameras can even record as many as 200 million frames per second, enabling us to watch atoms moving about – as long as we are replaying the footage in slow motion.

High-speed cameras are used in order to record events, that either take place in a very short time, that develop quickly, or both. They are in use whenever movements or the behaviour of materials, which cannot be perceived with the unaided eye or regular cameras, need to be analyzed.

While high-speed cameras can make fast motion-sequences visible, extremely slow events, like the growth of a flower, need a different technology to become visible. Special cameras which are shooting frames in regular intervals allow us to watch events which would take days, months and even years in a few minutes. Our special programme I spy with my little eye will show short and fast film clips, and even rewind on a few occasions in order to turn invisible moments visible.