Take 3 or 4 shots of the same sequence without changing any settings. View the histogram of each image and understand the sensitivity the camera has to the light by noticing the variations of the graph.
The Histogram is a bar graph that relates to image exposure. Divided into 3rds the graph records pixel information for dark areas (left), light areas (right) and midtones in the centre.
In a well exposed image, the graph reaches to each end of the chart showing that there is information in each of the dark, light & midtone areas. On the graph showing ‘over-exposure’ we can see the dark areas are flat and ‘spikes’ (clipping) appear at the lighter end.meaning the image is too light. If shooting in ‘jpeg’ detail will be lost. By shooting in raw mode detail can be recovered to lessen over-exposure.