Take three or four exposures of the same scene. Don’t change anything on the
camera and keep the framing the same.
Preview the shots on the LCD screen. At first glance they look the same, but are
they? Perhaps a leaf moved with the wind, the light changed subtly, or the framing
changed almost imperceptibly to include one seemingly insignificant object and
exclude another. Time flows, the moment of each frame is different, and, as the
saying has it, ‘you can’t step into the same river twice’.
Now bring up the histogram on the preview screen. The histogram is a graphical
representation of exposure – the camera’s sensitivity to light. As you page through
the images you can see small variations in the histograms. Even though the pictures
look the same, the histogram data shows that in a matter of seconds the world
changes, and these subtle differences are recorded by the camera. If you refine the
test conditions – shooting on a tripod to fix the framing, moving indoors and closing
the curtains to exclude daylight – still the histogram changes. Probably some of
the changes are within the camera mechanism itself; still, the camera is a sensitive
enough instrument to record them.
Add the sequence to your learning log with the time info from your camera’s
shooting data as your first images for Part One.
Exercise in practice
This was an interesting exercise to execute, it was a new experience to set the camera to Programme.
I chose a subject with quite a lot of contrast in it, as well as some strong areas of colour.
the three images where loaded to Lightroom and the histograms were copied using my iPhone. I am sure there is a better way to capture the histogram, but this worked in the absence of a better way.
The slight changes in light and framing can be seen in the work set out below. Indeed it is interesting just how much change there can be from moment to moment when seemingly taking an image of the same scene?