Do You Understand the Aperture-Shutter Speed Relationship?

Water Steps #2. Canon 70-200mm zoom @200mm, 1/2 sec @f18, ISO 50. (Copyright 2010 / Andrew Boyd)

Water Steps #2. Canon 70-200mm zoom @200mm, 1/2 sec @f18, ISO 50. (Copyright 2010 / Andrew Boyd)

Aperture and shutter speed, along with to a lesser extent, their little brother, ISO, rule my world.

Aperture and shutter speed have more to do with the decisions I make when shooting than virtually anything else. Because the shutter speed that you select, and the depth of field that you want (read aperture) do more to affect your results than any other choices you make.

I think this aspect of photography was all much easier to grasp back when we all shot with completely mechanical film cameras: you had a shutter speed dial on top of your camera. You had physical, mechanical aperture rings on all of your lenses. There was an ISO dial that you turned to change the light meter readings inside your camera (or your camera didn’t have such an advanced device, and you used an external light meter). You developed a visceral understanding of this all-important set of camera functions and how they interacted with each other.

This is harder now for young photographers. While most cameras now have some type of ‘wheel’ that you turn or spin to change shutter speed, the aperture rings on lenses are gone. Physical aperture changing is harder—‘don’t you just want to use ‘Program’ mode?’—and really learning to manipulate this aperture/shutter speed dance requires more thought and work.

The featured photograph in today’s post got me thinking about all of this. I was shooting at the water’s edge on Lake Pontchartrain’s north shore as a cold front was starting to blow in, creating a lot of interesting wave action. I was experimenting with different shutter speeds, trying to find the one that created the look and feel that I wanted: too long a shutter speed and the wave action all blended into boring; too short (fast/high) a shutter speed and the sense of motion and mystery was lost. In this case, 1/2th of a second @f18, ISO 50,  turned out to be the shutter speed/aperture combination that gave me what I wanted.

So if aperture and shutter speed don’t play a big role in your photography, they should. If you don’t shoot at least some of your photography on manual mode, give it a try. I promise you’ll learn some things about yourself and your own shooting that will be useful in your shooting, and maybe even change how your approach what you do.

Hi, I’m Andrew Boyd, a.k.a. The Discerning Photographer, and I hope this post has been interesting and informative. Please leave me a comment about it, let me know what you’d like to see more of on the site! You can also sign up for email delivery of all future articles or my RSS feed. Thanks!–DiscerningPhotog

Posted in: How To

About the Author:

Photographer, videographer and photo editor. Host and creator of The Discerning Photographer web site. Currently a Canon shooter.

6 Comments on "Do You Understand the Aperture-Shutter Speed Relationship?"

Trackback | Comments RSS Feed

  1. Kerri Barglof says:

    Thank you! I’m still grasping all the bDics and really appericiate your article!

    Have a blessed day!


  2. Jeffrey C. says:

    I am trying to figure out how to do this in a quick way. If you come up to a scene in NYC and want to take a quick photo, how do you decide what aperture and shutter speed? A couple situations to get a specific answer:

    1- A fruit stand on the corner (no movement just trying to capture the city) : how do i know what aperture/shutter speed/ ISO to use? and how quickly can you figure this out when on site. As oppose to the “easy” way out of just doing either Av, Tv or auto?

    2-a cab speeding down the street and you want to capture the movement of the cab – same questions as above

    3-kids playing sports in central park

    just trying to get a feel for how to really attack the situation when i am in it, and how to start the process of figuring out the right programs so i can stay in M mode and control the entire photo, however it can be overwhelming at first.

    also (since i just ready your post on the nikon d3100) can all of this be done with that?

    thank you! sorry for such a long post

  3. If you want to show the movement (#2), you need a slower shutter speed, thus a correspondingly higher aperture to compensate. Remember, it’s a push-pull, yin/yang relationship between the two. Go check out my post about shutter speed ( for more information.
    Your fruit stand example: I’d want to keep the aperture wide open (f2.8 or whatever) and use a faster shutter speed here to ISOLATE the fruit vendor from the background: the wide aperture will blur the background.
    Kids in the park: I want a fast shutter speed to catch the action.
    And your last question: all of this can certainly be done with the D3100.
    Good luck!

  4. Jeffrey C. says:

    thank you! As per my other post asking about a quality lens instead of the 18-55 “kit” lens for the d3100. I will be going with the Nikkor 50mm f/1.8D Autofocus Lens. Once I have some experience with that I will start to venture for the zoom lens. Which appears to be a much more expensive investment unless I go with a 70-300 f4-5.6.

    Thank you again!

Post a Comment