Learning about shutter speed (Part 1)

Time to move on to shutter speed.   Shutter speed tends to be the most straight forward of the three elements which make up overall exposure.   Shutter speed is simply the amount of time the shutter is open to allow light to pass through to the shutter.   Shutter speed can be extremely fast like 1/4000 of a second or on some cameras 1/8000 of a second to very long, like 30 seconds.   You can even push beyond 30 second exposures by using the bulb setting which allows you to open and close the shutter with clicks of the shutter release button.

For now we'll just focus on the range of 1/4000 to 30 seconds which is available on most consumer DSLRs.

Let's take the faster end of the matrix 1/4000 to 1/640 of a second.   One of the key benefits of fast shutter speeds is the ability to freeze motion.  

Freezing motion can be a lot of fun with kids.  

And it is great for action, like sports:

400mm  f/5.6   ISO 200  1/1000 exposure

Now on the other side of the spectrum is the slower shutter speeds.  There are a couple key benefits with slow shutter speeds.  Those are capturing images in low light and also creating motion blur to depict motion or to make water look 'dreamy.'

24mm  f/4  ISO 10,000  20 second exposure

This picture of the Milky Way requires a very long exposure in order to capture the light coming from all the stars.   This was not visible to the naked eye.  You can see the plane lights in the bottom of the frame from a plane passing during the shot.

13mm  f/10  ISO 100  10 second exposure

In the case of the Buckingham Fountain photograph, a long shutter speed of 10 seconds was used to create a dreamy effect of the water.

285mm  f/16  ISO 100  1/15 exposure

In this photograph of race horses passing by, a shutter speed of 1/15 second was used to create a feel of motion (panning was also used to try to keep some focus on the jockeys.)   You can see that a shutter speed of 1/15 was not fast enough to freeze the motion.

In part 2 we'll talk about using shutter speed in combination with aperture to get an accurate (properly exposed) photograph.