June 14, 2015

How Does Your DSLR's Shutter Really Work? This 10,000FPS Video Gives Us a Glimpse

Slow Mo Guys Canon 7D Shutter
Have you ever wondered what's actually happening inside of your DSLR when you take a photo?

It's one of those small things that's really easy to take for granted. You press the button, there's a clicking sound, and voila, you have yourself a photograph. But the amount of technology and engineering that goes into creating that photograph is pretty incredible. Need proof? Gavin over at The Slow Mo Guys (one of the most wildly entertaining and informative YouTube channels in existence) used a Phantom Flex to capture the mechanical shutter of the Canon 7D at a whopping 10,000fps. Needless to say, this should give you an entirely new perspective on what's going on inside of your camera:

Not only is this a fantastic explanation of how a mechanical shutter works at a variety of different shutter speeds, but it's also a great reminder of why we need to be wary of rolling shutters in the context of filmmaking. While digital cinema cameras with global shutters are becoming more common and affordable (hooray!), almost all video-capable DSLRs and mirrorless cameras still utilize a rolling shutter. For that reason, most of us still have to make sure to avoid things like whip pans and highly-kinetic camera movements because, as Gavin explains in the video, each frame of video actually contains multiple points in time due to the way the image is captured by the sensor (from top to bottom).

If you're interested in more awesome high-speed videos like this one, definitely head on over to The Slow Mo Guys YouTube channel.      

Your Comment

13 Comments

This is great. Defintely useful to help people understand flash sync speed limits.

In theory, shouldn't mirrorless cameras have faster sync limits?

June 14, 2015 at 5:09PM, Edited June 14, 5:08PM

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Brooks Reynolds
Director/DOP
355

Gotta say, as much crap as everybody gives Canon these days, my 7D has been a workhorse as well.

Very good video, thanks.

June 14, 2015 at 10:36PM

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Cool to see that shutter in slo-mo. It's true almost every single camera on the market today has a rolling shutter.
That's why I bought a Digital Bolex D16.

June 14, 2015 at 10:52PM, Edited June 14, 10:53PM

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Jeff Macpherson
Writer / Director
171

This isn't what rolling shutter is. Come on.

June 15, 2015 at 1:45AM

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Brooks Reynolds
Director/DOP
355

The time-delay effect of a vertical shutter was shown in 1912 in the famous French Grand Prix race car shot. I believe it was taken with a 5x7 focal plane shutter that, like the Canon, traveled from top to bottom, but much slower and for a greater distance across the giant piece of film. The race car's wheel leans forward and the poles and people in the background lean backward. It was so iconic, so representative of speed that cartoonists began drawing fast cars that way.

Rolling shutters are a very old problem indeed.

https://iconicphotos.wordpress.com/2010/03/06/automobile-delange/

June 14, 2015 at 11:07PM

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Again. This isn't what causes rolling shutter in DSLR video. And I dare you to show me an example of it in photography with a modern SLR.

June 15, 2015 at 1:46AM

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Brooks Reynolds
Director/DOP
355

Well the physical shutter isn't moving in DSLR video, but it's the same concept. You have a line of pixels being activated from top to bottom much like a physical shutter would expose film or even a digital sensor. It's more or less the same method of exposure causing the effect.

June 15, 2015 at 1:21PM

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Correct. The principle is the same but how it actually works is different. Conflating the two is misinformation that tends to be hard to shake in the camera world.

June 15, 2015 at 11:55PM

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Brooks Reynolds
Director/DOP
355

While you're correct that this doesn't cause rolling shutter, older focal plane shutters did cause something similar a long time ago. The photo I'm pointing to is an often-used example of the problems inherent with focal plane shutters. (In this well-known case, the effect was accepted as it added to the concept of "speed.")

http://people.rit.edu/andpph/photofile-b/lartigue-1.jpg

June 18, 2015 at 7:46PM

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great video. thanks!

June 16, 2015 at 12:29PM, Edited June 16, 12:29PM

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Einar Gabbassoff
D&CD at Frame One Studio
1001

Very interesting but what does the shutter on the 10,000 fps camera look like?

June 17, 2015 at 5:18PM

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Julian Richards
Film Warlord
1051

.

Wanna' see it again?

June 18, 2015 at 7:40PM

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I remember the olden days when focal plane shutters were two black fabric "curtains" that traveled horizontally, strictly mechanical with no electronic timing. And while I'm at it, get off my lawn.

June 18, 2015 at 7:39PM

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