Quick Tip: How Does Shutter Speed Affect Video?

Quick Tip: How Does Shutter Speed Affect Video?

on Feb 23rd 2013 with 13 comments

When talking about video, many people refer the “cinematic” or “videoish” looks. Cinematic is in. Everyone wants to make sure their videos look like they came from a Hollywood backlot. One of the most basic methods of changing the look is by controlling the shutter speed.

We all know the effects of shutter speed on stills, from long exposures more than eight seconds to 1/250th flash sync to 1/2000th action shooting. This flexibility isn’t available with video, however, as the slowest possible (though not necessarily available in-camera) speed is the reciprocal of the frame rate. So what should you be thinking about when adjusting your shutter speed? Here are five things to focus on:

1. 24 or 25 Frames per Second

If you’re shooting for that filmic look, you should ideally be shooting at 24 frames a second (or 23.976, as is often the case on HDSLRs). If you’re looking to shoot for TV, shoot at 25p (that is, 25fps, progressive scan) in PAL countries and 30p in NTSC countries. Usually regional firmware variants enforce this distinction anyway. Why does the frame rate matter? That takes us to point two:

videoshutter_01
The options available for frame rates on the Canon T3i. In this quick tip, I’m using 1080p24 and 720p60.

2. Shutter Angle and Shutter Speed

Shutter speed is also one of the aspects of the “film look.” If you’re aiming for cinematic, get used to thinking about shutter angle, and converting between that and shutter speed. Filmic images almost always use a 180° shutter angle, that is, half of the reciprocal of the frame rate. So a 180° shutter at 24p is 1/48 sec. The closest speed to this available on a DSLR is 1/50 sec.

Shutter angle originally was used with rotary shutters, but now must be translated to curtain shutters. 360° translates to a shutter speed of 1/the frame rate. 180° is 1/double the frame rate, and gets faster from there.

At 30p, it would be 1/60 sec. This look has been socially imprinted on us from decades of movies shot at 24 frames with a 180° shutter, and it’s a simple method of putting more apparent production value on-screen.

The other basic shutter angles are 360°, 90° and 45°. At 24p, these in theory would be 1/24 sec, 1/96 sec, and 1/192 sec. These of course aren’t precisely available on DLSRs, so you just have to use the closest one you can find.


Comparison of motion blur at 24p. Note that the 1/50th shutter speed tends to look the most “natural,” and the 1/200th looks uncomfortably crisp.

3. Under Normal Circumstances

Moving away from 180° shutter tends to look bad in most circumstances. Using 360° shutter (1/30 at 24p is the closest I can get on a T3i, 1/60th is available at 720p60, however) creates twice as much motion blur as we’re used to seeing, and gives the footage a vague quality which can look like bad night-vision video.

Going up to 90° and 45° shutter usually gives the picture an uncomfortably crisp look that’s usually referred to as the “video look” or looks “video-y.” This tends to be the result you get from cheap camcorders, news footage, or daytime TV. Generally not what we’re going after!

videoshutter_02
Crops of the video frames. Left to right: 360°, 180°, 90°, 45°. The length of motion blur relative to the width of the rice grains clearly halves between each interval.

4. Using Angles to Your Advantage

To every rule, there’s an exception. Other shutter angles can be used for effect, if done carefully and well. For example, the D-Day beach scene of Saving Private Ryan uses a 45° shutter with a modified film advance timing system in order to recreate the sharp, jerky quality of WWII newsreel.

In Gladiator, battle scenes were shot with a 45° shutter to create a stark, staccato feel, adding grit, literally. The dust particles showed up in sharp relief when they would normally blur out. If you’re trying to create a dreamy or intoxicated effect, 360° shutter could also be worth a try as long as you have sufficient camera stabilization.


At 60p, the motion looks strangely smooth, like a video game. See, however, that the 180° rule still applies.

5. High Speed Shooting

Finally, when shooting high-speed for slow motion video, the 180° shutter angle is still the best-looking option. Common sense says that when shooting at 60p to conform to 24p, a 360° shutter would be best to maintain approximately the same level of motion blur as a 180° shutter at 24p. However in practice, this doesn’t work, as our eyes understand the slow motion and still expect to see a 180° shutter angle along with the associated reduced motion blur.

This is related to a phenomenon called cadence, which is the amount or quality of motion of subjects between frames. Just like the 180° shutter angle itself, our media-saturated brains understand cadence well and adjust accordingly.


Oddly, the 360° shutter at 60p looks blurry, even though it’s about the same magnitude as 24p 180°. The motion doesn’t look so bad at 90° either; perhaps this is because action scenes are frequently shot at narrower shutter angles to reduce motion blur.

That’s it for now. Happy shooting! Comments? Questions? Hit up the comments below.

 
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Rob is a US-based artist and writer, mostly focusing on nature photography but occasionally catches the bug for something else. You can talk to him on the Twitters here and/or view his photography on 500px.  

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  • Georges Dutil

    What in the world are shutter angles, I can’t grasp the meaning of 45, 90. 180 degree angle as pertain to DSLR. Please clarify these concepts for me. Thank you!

    • http://twitter.com/rob_dwm Rob Taylor

      As I explained in point two, shutter angles come from the cinema world of rotary shutters: http://en.wikipedia.org/wiki/Rotary_disc_shutter

      The spinning disk has a slot cut out which allows light to hit the film. When this slot is half of the disk, so there’s just a spinning semicircle, that’s a 180 degree shutter. It allows light to hit the film for half of the duration that the film frame is in place. At 24 frames a second, the film frame is obviously in place for 1/24th sec. Therefore, the 180 degree shutter allows light to pass for half of this time which would be 1/48th sec. The closest to this on a DSLR is 1/50th sec, so you would use that as a 180 degree shutter.

      A 90 degree shutter is a quarter of the circle, so it allows light to pass for only a quarter of the time. At 24fps, that would be 1/96th sec. The closest to this on a DSLR is 1/100th sec, so you would use that as a 90 degree shutter.

      I did cover all of this in point two, however.

  • Loyal Renegade Films

    In current DSLR models, you can’t control shutter angle. Higher end cameras allow you to do so, but mainly you will use 180 degrees.

    • http://twitter.com/rob_dwm Rob Taylor

      Precisely. Hence why I described how to convert between the two. Technically no cameras other than film cameras, the F65 with optional disc shutter, and maybe one or two others I’m forgetting allow use of shutter angle, even if you can set the shutter speed in terms of angle. CMOS sensors use a rolling shutter, regardless of the software options. And yeah, that was my main thrust of the article, really- 99% of the time people should be using 180 deg shutter.

  • Pradeep

    May be a little table showing the shutter angles and corresponding shutter speed and the effect that can be achieved will put many of us out of misery.

    • http://twitter.com/rob_dwm Rob Taylor

      The shutter angles, speed and corresponding effect are demonstrated in the videos. They’re all an identical action so that you can compare across videos if you wish.

  • Andrew Childress

    I had been wondering about this on some video projects I’ve been planning. Thanks for the tip Rob!

    • http://twitter.com/rob_dwm Rob Taylor

      No problem Andrew, happy I could help!

  • Aaron

    Thank you for a very insightful article! I have known about quick frame rates looking “fake” for some time, but this finally explained why even when using 24 or 30 fps, a video still doesn’t look right. I will certainly use this tip.

  • David Markham

    This is a great insight presuming the camera is rock solid on a tripod. I recently shot some panning & tilting shots at 24fps at 1080p and the results were terrible. Really jumpy between frames. I switched settings to 30fps and the results were much better. (Perhaps it was hardware related: Nikon D800?)

    • http://twitter.com/rob_dwm Rob Taylor

      Interesting. While the Nikons aren’t usually the best for video, I haven’t heard about any issues like that- more just things like moiré, aliasing, or softness. If you want an in-depth comparison on the hardware in terms of video, my recommendation is the excellent as ever Philip Bloom’s FF shootout: http://vimeo.com/42065372. There may be some hints or tips in there as to your problem.

      My only other thought is the stabilisation- were you using a fluid head, and was it strong enough to support your rig?

  • Dale Estes

    Thanks for a great and informative article. I kind of understand about the shutter angle and all, but my camera, an older JVC GZ-HD7 only gives me 60fps 1080i. Should I use 1/120 shutter speed to get the 180 degs from 60fps, or 1/60 to get the 180 degs from 30fps that the video will eventually end up being?

    • http://twitter.com/rob_dwm Rob Taylor

      That’s an interesting question. My instinct is to say that because you’re not actually slowing it down at all, just combining the two interlaced fields, that you should shoot at 1/60th so that each field has the correct amount of blur for the final 30p footage to be 180 deg shutter.

      I’d be interested in seeing an empirical test on this though!