Beginner’s Corner – Managing Your Shutter Speeds
By Charles MacPherson–
Managing Your Shutter Speeds
Managing your camera’s shutter speed is absolutely critical to making sharp images – or to create motion blur when you want to. This Beginner’s Corner article will give you a solid handle on how to eliminate or make motion blur.
Think of the camera’s shutter as a window shade. It either prevents light from reaching the digital sensor (or film), or allows it. It’s right behind the mirror in an SLR. You can look, but DON’T touch – they’re very delicate and fragile.
The shutter’s function is really simple. The longer (or shorter) it stays open, the more (or less) light reaches the sensor.
Shutter speed is expressed in fractions of a second. 1/500th second is exactly what it sounds like. Take 1 second and chop it up into 500 equal parts. 1/500th of a second is one of those parts.
Shot at 1/3200th second!
Most modern SLRs have a shutter speed range of 30 seconds to 1/8000th second.
That’s all there is to it – except…
Except that the shutter speed has a direct impact on whether your image blurs. And there are two kinds of blur.
The first is camera shake and there’s a helpful rule-of-thumb you can use to be sure your shutter speed is fast enough to freeze motion blur caused by camera shake. Here it is…
For a hand-held, non-stabilized lens, shutter speed should be equal to or faster than the focal length.
Translated into English, that means that if you’re shooting with a 200mm lens without image stabilization (IS / VR / OS etc) or stabilization in the camera body (Sony), your shutter speed should be at least 1/200th second. 200mm, 1/200th second. Get it?
Then you can factor in your stabilization. For example, Canon’s 70-200mm f/2.8 L IS II claims (an incredible) 4 stops of stabilization. That means that at 200mm, you can divide that 1/200th second in half, 4 times, or a minimum shutter speed of about 1/12th second.
Personally, I find that awfully hard to believe. I’d stay with a more conservative 2 stop estimate, yielding a minimum shutter speed of 1/50th second.
Of course, if you are using a tripod, all bets are off. If it’s stiff and stable enough, your shutter speed could be days, not fractions of a second!
The second kind of blur comes from subject movement. There’s no fixed rule-of-thumb for this one, but I can give you some ideas. But whichever (my suggestions or focal length) gives you the faster required minimum shutter speed, use that value.
For people at rest, 1/60th or faster.
For people in motion (sports), 1/250th or faster.
Birds in flight – depending on the bird. Slow birds (Pelican, gull), 1/250th second or faster. Fast birds (warblers, swallows) 1/800th second or faster.
Cars in motion (create blur in the wheels), propeller-driven airplanes (create blur in the prop), 1/160th second or faster.
Helicopter (create blur in the blades), 1/125th.
Shooting from a moving vehicle (car or boat without excessive vibration), 1/1000th second
Shooting from a vehicle with excessive vibration (some boats at idle), Maximum available. Push ISO to reach at least 1/5000th second.
Now for the wildcard. Sometimes you want to CREATE blur. This is really a lot more art than science, so experiment!
Intentional blur in wildlife is one of my personal projects. The other is Swallows, and neither is especially easy!
Here’s one example…
A frenzy of sandpipers at takeoff – with an intentional, pleasing blur at 1/40th second
I created this image by closing my aperture to the point that I drove the shutter speed down to 1/40th second. Then I panned as the flock of birds took off. The trick to this is to hold the birds in the same position in the viewfinder – otherwise the entire bird will be too blurry.
One technique for making this easier is to shoot a burst. The first shot will tend to be blurrier as your finger mashing the shutter release will shake the camera. But keep that finger down and keep shooting, and subsequent shots will be more stable.
Here’s my favorite…so far!
A Red Fox with a stolen fish – and intentional motion blur.
I created this motion blur in a similar fashion as with the birds above. I closed the aperture until I drove the shutter speed down to 1/60th second.
So keep these suggestions in mind, and don’t be afraid to experiment!
Catch more gems from Charlie at <theamazingimage.com> and sign up for his newsletter that brings a wealth of technical and creative tips. Most important you’ll see his upcoming photo tours to some amazing spots in the USA and Canada.