Are the settings on your camera really so hard to understand? Of course not, but it can seem that way at the start, especially if they are not explained to you in simple terms you can understand.
For some photography snobs, shooting in manual mode is a badge of honor, shunning any other mode as something akin to cheating. I do shoot in manual mode, but I use Aperture Priority and Shutter Priority as my preferred modes of choice.
Typically represented by a capital A (or sometimes Av, short for Aperture Value) on the camera mode dial, aperture priority allows the photographer to dial in this specific exposure setting—the ƒ-stop—and asks the camera to calculate the correct corresponding shutter speed in the instant before the shutter is released. Before we get ahead of ourselves, let’s back up just a moment for a better understanding of how aperture priority mode works.
A camera has three primary exposure modifiers: aperture, shutter speed, and ISO. The aperture (also called ƒ-stop) is the size of the opening in the lens which modifies the amount of light that’s let into the camera.
The shutter speed modifies the duration that light is let into the camera.
And the ISO (or film speed, back in the old days) represents how sensitive to light the sensor will be. A higher ISO is more sensitive to light (and produces more noise) while a lower ISO is less light sensitive but produces a cleaner signal and better image quality. These days, though, sensor technology is so good that even high ISOs still look great.
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It’s by adjusting these three settings in combination that proper exposure is established. If you allow in less light with a smaller aperture, you’ll need to balance it with more light from a longer shutter speed. Add to one, take away from the other. Simple, right?
Well, sometimes it’s not so simple, particularly in situations in which the light is changing. This could be when I’m photographing in full sun then moments later in shade. These changing situations make automatic exposure modes more convenient than continuously recalculating the correct manual exposure.
But rather than turning over all the control to the camera, modes such as Aperture Priority and Shutter Priority allow the photographer to retain manual control over one specific setting. In this case, it’s Aperture Priority, where the photographer sets the ƒ-stop and the camera calculates the correct shutter speed to accompany it.
Aperture Priority mode is particularly helpful in situations where the photographer wants to set a specific depth of field and have that setting take priority over the shutter speed.
Aperture Priority is my mode of choice with landscape photography. To create a sharp image area through greater depth of field the photographer can dial in a tiny aperture such as ƒ/22, and in Aperture Priority the camera will determine which shutter speed will produce the correct exposure. Be warned, though, that in this case, a tripod may be necessary if low light requires a long shutter speed that’s too long to handhold.
Now that we understand the way Aperture Priority mode works, we’ll look at its counterpart on the automatic exposure spectrum: Shutter Priority exposure mode.
Often represented by an S or Sv on the camera mode dial, Shutter Priority mode sees the photographer dialing in a manual shutter speed and leaving the selection of the appropriate aperture to the camera’s brain.
As with any automatic exposure mode, Shutter Priority is particularly helpful in changing light situations, though it’s useful in any situation in which it’s the shutter speed you primarily want to control.
For instance, when I’m shooting birds I want at least 1/500th, I can set the shutter speed in Shutter Priority and let the camera pick the correct aperture to accompany it.
Be aware though if your shutter speed is too fast for the available light you may end up with underexposed images. This can be corrected by dialing in a higher ISO.
Great photography is about depth of feeling, not depth of field.