The Fascinating History and Confusing Reality of Shutter Speed

Filmmaker Alan Melikdjanian, known by millions of fans as “Captain Disillusion” on YouTube, creates entertaining and educational content where Captain Disillusion reveals the truth surrounding video effects and editing. Captain Disillusion also regularly dives into camera technology, as in his latest video all about shutter speed.

While the idea of getting accurate, in-depth technical information from a man dressed like a tracksuit-wearing superhero may be slightly off-putting to first-time viewers, it is well worth giving Captain Disillusion a chance because he’s not only entertaining but extremely knowledgeable. And when it comes to shutter speed, especially in the realm of videography, people need all the help they can get. It’s an extremely confusing topic.

“There’s no such thing as infinity in the physical world. Just as the tallest mountain has a peak, a snapshot of the tiniest moment is actually a record of a period of time,” Captain Disillusion explains. “In cameras, we call the setting that controls that period ‘shutter speed.’ Why? As usual, because of olden times.”

“The earliest cameras were just a box. You uncovered a lens, let light accumulate inside for a tedious amount of time, then covered the lens back up.” Captain Disillusion jokes that this made selfies “extremely challenging,” as early photosensitive materials were not all that sensitive. Necessary exposure durations rapidly decreased as technology improved, moving from many minutes to just a few seconds and, eventually, to fractions of a second.

Even on modern digital cameras, photographic shutter speed is still denoted relative to seconds, which makes sense, but can feel obtuse when shooting action at 1/4,000s, or in the case of a camera like the new Sony a9 III, as fast as 1/80,000s. In that extreme case, the “shutter,” although there is no physical shutter as such in the a9 III, is “open” and exposes pixels to light for 0.0000125 seconds. Oh how far we have come.

As Captain Disillusion explains, as the required exposure times decreased in response to improving photographic film, or other mediums, the demand for precision control over exposure time increased. Numerous solutions came and went, including guillotine-style shutters and Packard shutters, although Packard-Ideal Shutter Company still exists and makes custom shutters. Other solutions have stuck around in the mainstream, including leaf shutters and focal plane shutters.

Then came motion pictures, which upended shutter design and how people frame “shutter speed” entirely. Enter the rotary shutter, and the idea of “shutter angle.” The shutter angle is a way to describe shutter speed relative to frame rate. At its most basic level, original rotary shutters included an angled opening that would allow light through to the film plane each time the rotary completed a revolution. The larger this angle, the slower the shutter speed, up to a full 360 degrees where the shutter speed would be as slow as the frame rate of the motion picture camera. Although shutter design has changed significantly over the decades, shutter angle terminology and what it means concerning motion blur persists.

In his new video, Captain Disillusion explains all this and much more, like rolling shutter. Watch for a PetaPixel appearance when Captain Disillusion talks about electronic front-curtain shutter and bokeh.

He has also made videos about aspect ratio, frame rate, resolution, and color, which will surely be of interest to photo and video enthusiasts. Anyone interested in seeing a silver-painted man in a yellow tracksuit debunk viral internet videos should also check out Captain Disillusion’s YouTube channel.

Image credits: Featured image is an illustration by MikeRun licensed under Creative Commons (CC BY-SA 4.0 DEED)