kcbrown wrote in post #4165859
EC means "exposure compensation". The idea is that the camera will generally expose so that the average of the metered intensities in the scene comes out to "middle gray".
If you're shooting a scene where you know that the average should be lighter than "middle gray" then you can add some exposure compensation (move the little needle to the right of center) to make the scene come out properly. Such a scene might be, for instance, a person in light clothes standing in front of a white wall. The camera would underexpose that scene without exposure compensation -- it would try to make the whites look more like gray. Similarly, place a person in dark clothing in front of a dark wall and the camera would normally overexpose it (by trying to make the blacks look grayish in intensity), so you'd have to put in some negative exposure compensation (move the needle to the left of center).
A lot of this will depend on the metering mode you're using, but the metering mode tends to primarily change what is being metered more than how it's being metered.
Bryan Peterson's
Understanding Exposure is a good book on this subject.
Hope this helps...
I'd like to add a slighly different alternative technique to the valuable advice given here.
KcBrown makes what is one of the most important points in modern exposure systems: when the camera meters an area to be exposed, whether spot exposure, evaluative, centered, or average, it is calculating for a "tonality" of medium gray. What that means in practice is that if you expose for a lighter-than-gray area, the camera will tend to underexpose to render that area as medium; if you expose for a darker-than-gray area the camera will over-expose.
With that in mind, there are times when we can have a little more control than using the Average and estimating the overall tonality of the scene. Let's say you have an area in your field of interest that you can identify as medium, dark, or light, and that you can fill all or most of your center "exposure circle" with that area. If you put your camera in spot focus, it will automatically create a "medium" exposure for that center. If it's snow, for example, the camera will underexpose to render it grayish -- you know this, so you can stop up your expose, up to a couple of stops, to make the snow white.
On the other end, if your center is dark or black, you know you can stop down your exposure to make it the proper tone.
This technique has worked well with me when I wasn't sure how to interpret a whole scene, but I had a portion of the scene that I could interpret. For expample, on a recent trip to Mount St. Helens, I was pleased to find a nice patch of medium-gray cloud around the top of the mountain in the middle portion, so I didn't even have to do an exposure lock and recompose or even use EC. In that case, I was confident to let the camera expose for medium gray. In other instances, I've used either manual or aperture priority EC Using this method you'll frequently have to use exposure lock and recompose when your exposurecircle is not dead center for your shot, but it does give a bit of thoughtful control!
Hope this helps!
Tony