Welcome back to this multi-post discussion of camera exposure. We’re headed for the final turn with the finish line in sight.
Recall that our first post introduced the Exposure Triangle (ISO, shutter speed, aperture). We used a bucket of water and hose analogy to describe the interplay between the three exposure “knobs” you have control over. The photo below was used to display two vastly different aperture settings.
The second post discussed the use of ISO settings which determine the light sensitivity of the sensor or film in your camera. Recall that camera improvements in high ISO performance have led to a new paradigm allowing pictures that could not have been captured just a few years ago such as this photo of Rebecca and Jeremiah in the NICU at Mission Hospital.
We wrote two posts which discussed slow shutter speed. In the first of those we introduced camera shake as the villain responsible for many of your unusable photos.
We also introduced a rule of thumb defining minimum shutter speed (i.e. you must keep your shutter speed at or higher than the focal length (aka zoom) of your lens). Check that post for some examples of this.
The second post on shutter speeds introduced some creative uses of long exposures.
It also introduced a very useful and intermediate-level skill called “dragging the shutter” to help reveal background elements when photographing with flash.
Today we will finish our review of shutter speed by discussing fast shutter speeds. It will come as no surprise that fast shutter speeds are used for freezing motion in scenes with fast moving subjects. You may recall from this post that flash can help to freeze motion. Today we’ll limit our discussion to stopping action using fast shutter speeds.
Photographers at athletic events typically use fast shutter speeds. The photos at this equestrian event were shot with a shutter speed of 1/2,500 sec which, if you’re so inclined, is 400 microseconds. A moderate shutter speed (say 1/500 sec) would not have resulted in a tack sharp (pun intended) photo.
However, the surfers below were photographed at 1/500 sec with very acceptable freeze motion results.
The photos of Destiny jumping from a bench show an interesting affect – both were taken at 1/100 sec. For the left side panel 1/100 is adequate (barely) because her motion is reduced at the peak of her jump. The same shutter speed is not nearly fast enough for the right hand panel. Her motion is greater at that moment as she accelerates to the ground. Hence, there is an obvious increase in the subject motion blur. Hey, it’s just physics, right?
Of course you don’t need a jumping subject to incur unwanted motion blur. In the photo below a family friend leans over to laugh with another friend. Notice the blur caused by the motion of her hands and hair. I should have minimized the blur by turning up the ISO to allow photographing with a faster shutter speed.
Here are a few other photos showing the utility of fast shutter speeds to capture and freeze motion – whether it be the Blue Angels, a kayaker navigating the rapids or Supercross and/or Moto-X superstars.
As a segue to next week’s post I show the two photos below. In both the fast shutter speed allowed me to shoot with the aperture wide-open. Shooting this way results in a limited Depth of Focus (DoF) – the topic of next week’s Tuesday Photo Tip.
Feel free to comment or show off some of your own compositions that illustrate this tip. In the meantime, stay tuned because next week’s post begins coverage of aperture values. Better yet – be updated automatically by “friending” our Facebook site.
PS - This is one of dozens of photo tips in our continuing Tuesday Photo Tips series of posts. There are other resource articles on our site you may enjoy covering basic and more advanced photography topics. There are also tips covering topics such as preparing for family or infant/child portrait sessions. If you would like a topic covered just jot it down in a comment or send us a note.