Aperture Vs. Shutter Priority

How to Use These Useful and Versatile Exposure Modes

by Peter K. Burian

SHUTTER MOTION (click to enlarge)
SHUTTER MOTION (click to enlarge)
© Peter K. Burian
All Rights Reserved
QUESTION: I want to get off shooting in the green AUTO mode but I find Manual mode too complicated; a lot of my photos are severely overexposed or underexposed. A friend recommended Aperture Priority and Shutter Priority modes. They sound good but can you explain how they work?

Answer from Peter K. Burian:
These two modes are very useful and versatile. They're the best options for greater control when you're ready to progress from fully automatic picture-taking. Here's how they work.

Shutter Priority (abbreviated as S or as Tv depending on the camera) is semi-automatic. This one allows you to set a desired shutter speed for motion control. The camera then sets a suitable aperture. For example, you might want to set 1/500 sec. to render a cyclist as "frozen" or 1/4 sec. to render a waterfall with an effect of fluid motion. (Naturally, you will need to use a tripod at such a long shutter speed to prevent blurring caused by camera shake.) If you decide to change the shutter speed, the photo will not get darker or brighter; the camera will change the aperture to maintain the same exposure.

PLANES DEPTH (click to enlarge)
PLANES DEPTH (click to enlarge)
© Peter K. Burian
All Rights Reserved
SHUTTER MOTION (photo at upper right): Shutter Priority mode is ideal for use when your primary creative intention is the control of motion. For these photos, I used a slow shutter speed for blurring the motion and a 1/500 sec. shutter speed to freeze the motion. A +1 exposure compensation setting prevented underexposure. (c) 2013 Peter K. Burian


Aperture Priority (abbreviated as A or as Av depending on the camera) is also a semi-automatic mode. You set the desired aperture, such as f/22 for an extensive range of acceptably sharp focus (depth of field) or f/4 for a more blurred background. The camera then sets a suitable shutter speed. If you set a different aperture, the camera instantly changes the shutter speed to maintain the same exposure (image brightness).


PLANES DEPTH (photo at right): When depth of field -- the range of acceptably sharp focus from foreground to background is particularly important -- Aperture Priority mode is an ideal choice. For these photos, I used f/4 and f/22 in order to achieve entirely different effects. (c) 2012 Peter K. Burian


If you take a photo and it's too dark or too bright overall, you can modify the exposure using the camera's exposure compensation +/- control. Set +1 perhaps for a brighter photo and -1/2 (-0.5) when first experimenting with this feature. Then take the shot again. Later reset exposure compensation to zero when you no longer need it.


Hint: Although the exposure should be the same in any aperture or shutter speed with the semi-automatic modes, there is one important point to remember. If the camera produces blinking numerals in the viewfinder, it cannot provide a good exposure at the settings that you had made. (Most often the problem is caused by a high ISO setting on a bright day or a low ISO setting in a dark location when using Shutter Priority.)

In other respects, both of the semi-automatic modes are easy to use and they allow you to control the most important creative aspects in serious image-making.


Learn more about photography...

Peter Burian teaches three interactive online online courses at BetterPhoto's school of digital photography:


In addition, Peter's photography appears in two books co-authored by Jim Miotke and Kerry Drager: The BetterPhoto Guide to Creative Digital Photography and The BetterPhoto Guide to Photographing Light.



Article by Peter K. Burian. To learn more about photography, explore the many online photography and Photoshop classes offered here at BetterPhoto.com.