Watch this demo of camera mechanics at 10,000 frames per second


#1

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#2

Which is also why these kinds of cameras have a sync speed above which you can’t illuminate the entire frame with a single brief flash of light: there ceases to be a moment when the entire frame is exposed all at once.


#3

It’s nice to see it work.

I had the privilege recently of dismantling an old Canon EOS Rebel film camera. They don’t sell when listed on ebay for $10, so I figured it’s fair game for taking apart.

The joy of taking apart a camera is that you can see and touch all the fiddly bits without worry, to learn how they make that shutter work so fast. It turns out that the shutter leaves are the flimsiest metal you’ve ever seen. It also turns out that the camera has hundreds of little parts, each of which clearly took many hours of engineering time, and nearly all of which are utterly useless for any other purpose.


#4

Since animation originally conceived of frames as instantaneous points in time with key frames being key poses rather than frames being durations of time they had to do a little kludging to shoehorn motion blur into CG and look ahead or behind to other frames for velocity information rather than having an open and close shutter time within each frame.
http://www.digitalartform.com/archives/2005/06/motion_blur.html


#5

Is there such a thing as a mechanical global shutter?


#6

Yes, and every camera salesclerk had to explain this over and over and over to the customers who were convinced that the photo lab managed to develop only horizontally half of every frame on the film.

/The Nikon F2 had a dimpled horizontal titanium shutter that could achieve 1/2,000 of a second, traveling a 50% greater distance at a much faster speed, than that Canon camera, with its multiblade/segmented shutter can. A superb piece of mechanical technology.


#7

Turns out that I knew only half of how an SLR works: I didn’t know about the rolling shutter. I thought the digital cameras were taking the whole image off the sensor at once. Makes perfect sense once you know about it, though.


#8

The ones with a global shutter do. But these chips are more expensive than the rolling-shutter ones.


#9

Between lens shutter. Most professional cameras have lenses like this as an option. The Mamiya C330 TLR had between lens shutters on all its lenses, which made it very good for recording moving subjects with minimal distortion, along with flash sync to 1/500th sec. I miss mine but film is just impossibly expensive nowadays.

I had an F2, nice camera but the actual shutter speed was nothing to write home about by modern standards. As I recall the maximum flash sync (full aperture exposure) was 1/80th sec, which means the shutter was quite slow in modern terms - later 35mm cameras had shutters to 1/300 second, nearly 4 times faster. The FM2 (which I also had, and which had a titanium shutter) was 1/200 sec.
Titanium is not that magical. There are now aluminum alloys which are stronger and much less dense than titanium, and these get used for shutters.

Incidentally, the shutter shown is not a rolling shutter. That was the earlier Leitz type which had two curtains that started their travel at slightly different times. Contax came up with a vertical rolling shutter using metal blades, but it was highly unreliable; oddly the Russians copied it (in the Kiev) and did a slightly better job.


#10
  1. The F2 was from the early seventies, remember? The typical flash synch speed in those days was 1/30 sec, 1/45 if you were were lucky. 1/80 was quite remarkable at the time - and with a horizontal shutter, no less.
    Of all the cameras I’ve used, it was the quickest to use and the most ergonomic. My hands felt quite at home from the first instant I held one.

  2. Those ‘between the lens’ shutters were called leaf shutters in those days. Electronic flash synch was really quite simple - the flash fired when the shutter reached maximun opening.

  3. Rolling shutters date from old glass plate/sheet film cameras. If you can find a Graflex, take a look at it. The shutter was a long roll of fabric which had a number of slits of varying widths throughout. The needed width was wound up to the top of the frame and the slit was dropped (usually using a spring-loaded device) across the plate. It could take a half a second or more to travel across the plate.


#11

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