Should I Use Auto Exposure Mode?


Digital cameras have been around long enough that they have inherited controls from times before digital. The Auto mode is one of them. This mode is a form of intelligent point-and-shoot mode and some wonder if they should use it. While I often turn up my nose at scene modes, I do use Auto mode. What’s the difference?

Figure 1 – The Auto exposure mode on a Nikon camera’s mode dial

In a sense, the Auto mode found on the camera’s mode dial (small green camera), or in a menu on the monitor, turns the camera into a point-and-shoot model (figure 1). What makes it different from the scene modes? Auto mode is a generic mode designed to let the camera intelligently sense what is going on in front of the lens and get a good picture. The camera makes all the exposure decisions, as with a scene mode, except it is a one-mode-for-all-scenes solution.

When is Auto mode appropriate?

When I am at a party and simply want excellent pictures I often switch to Auto mode, put a small external flash unit on my camera, and blast away. The intelligent camera and flash does all the work as I walk around having a good time with my friends and family.

Why am I not ashamed of using Auto mode in certain circumstances? Merely because I have taken the time to understand how my camera works, mastering things like shutter speed and aperture settings, and now just want to take some nice pictures. I am not ashamed to use the technology built into my powerful camera.

However, when I start shooting a wedding, graduation, or event, I won’t be doing it in Auto mode. For those times when the camera is there for fun, Auto mode works very well; but not so much for commercial shooting.

However, let me qualify that. If I were an inexperienced photographer who had been asked to shoot a wedding and felt inadequate, I wouldn’t hesitate to switch to Auto mode. The camera is capable of making good images, even if I’m not—yet. Use the technology when you need to, that’s why it is there. I don’t think I would take the time to start fiddling around with scene modes, to me that is going too far. However, Auto mode is a one-size-fits-all solution that can help you in emergencies.

If I couldn’t get my normal experienced partner to shoot an event with me on short notice, I wouldn’t hesitate to hand one of my cameras to a semi-enthusiast photographer friend, with it set to Auto mode, and ask for his or her help in shooting the event. Today’s cameras will perform.

What are some drawbacks to Auto mode?

There are some “gotchas” when using Auto mode. One of them is image noise. In Auto mode the camera has full control of aperture, shutter speed, and ISO sensitivity. It will keep the ISO sensitivity low (under 800 ISO) until an aperture and shutter speed combination will not give it a good exposure. Then it will increase the ISO sensitivity to “get the shot.”

Higher ISO sensitivity can add digital noise to the image, decreasing its quality and lessening the image sharpness due to internal noise reduction blurring of the image. It will get an image when you press the shutter-release button; however, that image may have some problems due to high ISO settings.

Also, in Auto exposure mode you lose control of the flash. The camera decides when it has enough light or not enough and will fire the flash accordingly. If you happen to be shooting a group shot with a bright background, you may want the flash to fire to light up the group properly, but the camera may see that bright background and refuse to fire the flash, even though it is turned on. Now you have a silhouetted group with no facial detail and a perfectly exposed background.

Or, you may prefer to shoot an ambient light (no flash) close-up shot of a bride’s beautiful rings, but the camera fires the flash. You remove the external flash unit from the camera’s accessory shoe on top, yet now the popup flash fires. No ambient light shot for you! The camera figures you don’t know what you are doing since you have it set to Auto mode, so it wants to protect your images.

The point of all this is simple. Use the amazing technology of the camera when you really need it. Otherwise, don’t! You lose creative control when you use any fully automatic modes. You turn creative control over to the assumptions made by the software algorithms put into the camera by a programmer somewhere. That programmer may not even be a photographer. In fact, the programmer may even use a stinky little point-and-shoot model and not even care when there is noise in his or her pictures.

Wouldn’t you rather control the final outcome of the image? Don’t settle for Auto mode. Use it while you are learning your camera, when the images are for fun, or in a dire emergency. Otherwise, “make” the images yourself. Don’t leave it to the camera’s software!

Keep on capturing time...
Darrell Young