You don’t have to shoot in Manual mode to take complete control over the exposure process.
When you use shooting modes other than Manual, the camera will set at least one of the three exposure controls (shutter speed, aperture, and/or ISO) for you. However, your camera provides you with an override called exposure compensation. It gives you the ability to change the camera’s exposure values from something other than what the camera automatically sets for you. In this article, I will show you how to use it to get the exposure you want every time.
When should you use Exposure Compensation?
First, let’s back up and talk about when you might want to use exposure compensation. You may wonder why you’d want to change anything, if your camera is already determining the proper exposure level.
The first reason is that your camera’s meter can be fooled by some of the conditions you face. The meter operates by looking at the tones in its view, then averaging them out. Basically, the manufacturers have determined that most scenes will average out to a middle grey tone, often referred to as 18% grey. Therefore, if the tones in your frame are darker than this middle grey tone, the meter will show that there is not enough light for a proper exposure, and therefore the meter thinks your picture will be underexposed.
Conversely, if the tones in your frame are lighter than middle grey, the meter will show that there is too much light for a proper exposure and it thinks your photo will be overexposed. A lot of the time the camera meter is right, but sometimes it is not.