Activate the histogram view
If you’re using an SLR in live view mode or you have a compact camera or compact system camera the histogram view can show you whether you have the correct exposure settings selected before you even take a shot.
Alternatively, if you’re composing images in the viewfinder of the SLR you can view the histogram when you review an image.
The histogram is a graph that shows the brightness of the pixels in the scene with the dark pixels being on the left and the bright ones on the right.
If the correct exposure settings are selected for the ‘average’ scene the histogram will have a ‘normal curve’ shape that looks a bit like a hill between two valleys, with a peak at the centre.
Generally you want to avoid having a peak at the extreme left or right of the histogram as this indicates that the shadows are very dark (peak to the left) or the highlights have burned out (peak to the right).
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