Balancing exposure in scenes that have a wide contrast in tonal ranges can be extremely challenging. The one thing you should never do is overexpose your skies to the point of blowing out your highlights (unless, of course, that is the look you are going for). It’s one thing to have white clouds, but it’s a completely different, and bad, thing to have no detail at all in those clouds. This usually happens when the camera is trying to gain exposure in the darker areas of the image (Figure 7.8).
With this feature, you can force your camera to choose an exposure that ranges, in one-third-stop increments, from five stops over to five stops under the metered exposure (Figure 7.9).
The one way to tell if you have blown out your highlights is to turn on the Highlight Alert, or “blinkies,” feature on your camera. When you take a shot where the highlights are exposed beyond the point of having any detail, that area will blink in your LCD. It is up to you to determine if that particular area is important enough to regain detail by altering your exposure. If the answer is yes, then the easiest way to go about it is to use some exposure compensation.
Using Exposure Compensation to regain detail in highlights
- Activate the camera meter by lightly pressing the shutter release button.
- Using your index finger, press and hold the Exposure Compensation button to change the over-/underexposure setting by rotating the Command dial.
- Rotate the Command dial counterclockwise one click and take another picture (each click of the Command dial is a one-third-stop change).
- If the blinkies are gone, you are good to go. If not, keep subtracting from your exposure by one-third of a stop until you have a good exposure in the highlights.
Adjusting Exposure Compensation
- Press the Exposure Compensation button (which has a +/- symbol on it) on the top of the camera to adjust exposure by -5 to +5 stops.
- Hold the Exposure Compensation button while rotating the Command dial to the left to increase exposure and the right to decrease exposure. Each right click of the Command dial will continue to reduce the exposure in onethird- stop increments for up to five stops (although I rarely need to go past two stops).
It should be noted that any exposure compensation will remain in place even after turning the camera off and then on again. Don’t forget to reset it once you have successfully captured your image. Also, the Exposure Compensation feature only works in the Program, Shutter Priority, and Aperture Priority modes. Changing between these three modes will hold the compensation you set while switching from one to the other. When you change the Mode dial to one of the automatic scene modes the compensation will set itself to zero.