Exposure 4: Shutter speed.

[RichardTaylor]

Shutter Speed.

The Shutter
Controls how long the sensor is exposed to the light.
The shutter is like a door in front of the sensor and is normally closed and only opens for the exposure.
The time the shutter is open is expressed in seconds or fractions of a second.

Shutter speed settings.
(1) Must be set to ensure correct exposure along with aperture and Sensor ISO settings.
(2) Must be fast enough to prevent camera movement resulting in un sharp photographs.
When hand holding, a guideline is that 1/focal length of the lens (in 35mm terms) = the shutter speed.
On a consumer SLR the sensor is smaller than a film (35mm) sensor
So with 18-55 "kit lens" lens (28-80 mm in 35mm film camera terms) the shutter speed used should be 1/30 second at the wide end and 1/75 second at the long end or faster.
If the camera/lens that has image stabilistion or vibration reduction than these shutter speeds can be reduced (see your camera/lens instruction book)
(3) If required must be fast enough to stop subject motion.
(4) Can be used creatively eg, subject motion and panning.

Examples:
(1) 1/10 @ F6.3, ISO 1600
This was shot hand held with an image stabilised lens.
Notice the scene and onlookers are sharp, however the shutter speed wasn't fast enough to freeze the motion of the walking girls.



(2) Here the relatively high shutter speed, 1/500 second, has frozen the action. The rider was ok.

Camera Canon EOS 40D
Exposure 0.002 sec (1/500)
Aperture f/10
Focal Length 400 mm
ISO Speed 400

(3) Relatively slow shutter speed, 1/100 second, and smoothly tracked vehicle whilst shooting (panning). Notice the wheels are blurred, as well as the background.

Camera Canon EOS 5D
Exposure 0.01 sec (1/100)
Aperture f/16.0
Focal Length 80 mm
ISO Speed 100

(4) If the camera is supported by a tripod, or some other object, you can shoot at much longer shutter speeds. In this case 3 seconds.



Camera Canon EOS 5D
Exposure 3.2 (Seconds)
Aperture f/8.0
Focal Length 45 mm
ISO Speed 200
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The main thing to remember it is a "balancing act".

ISO, shutter speed and aperture all work together and normally if you change one you change the other.
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This series

#1 Introduction to exposure - A balancing act.
Exposure (1) A balancing act
#2 ISO and introduction to aperture.
Exposure (2) ISO + Intro to Aperture
#3 Aperture
Exposure (3): Aperture
#4 Shutter speed

#5 Putting it all together.
Exposure 5: Putting it all together

Future posts in this series will include more detail on;
White balance
Exposure compensation

Thanks for looking.
Feel free to ask questions and feedback would be appreciated.
Richard

[Aleix]

Thanks for sharing. Good examples there, concise and easy to understand. Nice pictures, btw

[RichardTaylor]

Thanks very much.

[maulin]

Looking forward for further tutorials from you.

your guidance is highly appreciated.

thanks
maulin

[Hill Country Hack]

Nice set. Did you notice in the first image the guy in the brown shirt and glasses "checking out" the girls walking by?

[RichardTaylor]

Thanks.

I soon as I loaded up into my PC.
Not everybody sees that.

[PhotoHues]

Thank You.

[RichardTaylor]

Glad to help out.

[ceil 1940]

Richard I just finished this tute and it was excellent. You've made me realize I don't use my ISO setting often enough as a tool.

[autofocus]

Great of you to do this, Richard. Thanks for taking the time and effort to share this information...you are a real asset to the DPS community