Manual or Automatic

How do you tend to set your camera? Automatic? Aperture Priority? Shutter Priority? Full Manual? Beginners tend to set everything to auto and hope for the best, or at least to get one keeper out of many shots. This works fine when it works, but it lends no control. Hopefully this tip will relieve your fears of leaving auto mode and give you some understanding of aperture and shutter sped and how they interplay.

First, what do the aperture and shutter speed do? Shutter speed is easy. Well, they both are, actually, but shutter speed seems easier. The faster the speed, the faster the camera takes the shot. A fast shutter speed freezes motion, a slow shutter speed blurs motion. Common examples of this are with flowing water. A slow shutter speed blurs the water for an appealing, flowing look.

Money Creek #1

At times, though, the dynamics of water are best illustrated using a fast shutter speed, such as when catching the power of crashing waves.

Kilauea Point National Wildlife Refuge, Waves Breaking

But a fast shutter speed also lets in less light since the shutter is open for less time than a slow shutter speed. So, in order to get in enough light during a fast shutter speed, the aperture must be opened for proper exposure. This lessens the depth of field, or the region of the image that is in focus. The opposite is true for a slow shutter speed. Since much light is getting in during the shot, a smaller aperture must be used to compensate. This widens the depth of field. For landscapes this is generally what is desired, but not always. Ultimately the photographer wants to be able to control all aspects of the shot. We must work with the light we have, though.

For situations where the light is brighter than we would like for a slow shutter speed, the light can be cut using filters. For landscapes I almost always use a circular polarizer, and tend to use B+W filters. This cuts two to three stops of light. Neutral gradient filters of various strengths can also be used to cut light without imparting a color cast. For scenes that are too dark, fast shutter speeds are not possible without external lighting.

What is a stop, you ask? Stopping down one stop is reducing the light in half. Up one stop is double the light. This can be done with shutter speed, aperture, or a combination. For example, changing the aperture from f11 to f22 reduces the light in half. Going from 1/60 second shutter speed to 1/120 second also reduces the light in half.

So now we get back to the camera settings. First, automatic. The camera looks at the scene, primarily the amount of light, and sets the aperture and shutter speed for you. Not the depth of field you wanted? Too bad. Wanted the shot to focus on the foreground subjects with the background blurred, like these tulips below? Maybe the camera set itself up correctly.

Tulip Field Trio

Or perhaps you wanted large depth of field, as in this wide angle landscape.

Skagit River, Cascade River, Bacon Peak

You just have to hope for the best. Sure, some cameras have auto modes like portrait or landscape that will aid you, but why not learn how to set the camera yourself?

This brings us to aperture priority. You set the aperture, the camera sets the shutter speed. This works pretty well if you know the depth of field you want and the scene is easy to expose. If the shot is people standing in a green field with nice, warm side light, no problem. The camera will most likely do a great job. But what if the field is full of white daisies? Or even worse, they are standing in snow? Or black lava? These will throw your light meter way off. Sure, you can compensate with exposure compensation, but that is just another step and removes the ease of the aperture priority.

Next is shutter priority. You set the shutter speed and the camera sets the aperture. Taking pictures of a football game? This is a pretty good way to go. Set the speed fast and let the aperture fall where it may. But for flowing water or a landscape subject, you lose all control of your depth of field.

Now we get to manual. You set the aperture for the depth you want, look through the lens at the light meter, and adjust the shutter speed for a good exposure. If the shutter speed is not what you wanted, either change the aperture or use filters or external lighting, as the case may be. In the end, particularly for landscape work, manual affords the most control and results in the most shots turning out just like you intended.

The best practice is to practice. Play with the settings. Test the meter. Test metering modes. Test various apertures and check the depth of field. Look at the shots on your computer and take note of the settings you used. This kind of practice will pay off, both in your comfort with your equipment, and, most importantly, your ability to get the shot.

P.S. I will save the workings of the light meter for another day.