Update to original post
As I noticed when reviewing test results below, the camera set to full auto (the general rule for this component of the course) meant an automatic change in the shutter speed for 1 of the pictures below. This still illustrates the sensitivity of the camera to changes over a few short seconds, but doesn’t produce comparable histograms. It is a reminder to always think about settings before shooting! Attached immediately below are photos with the camera set to manual, with no changes between each picture. The differences in the histograms are subtle (at low light), but nonetheless noticeable.
This is an exercise in understanding the sensitivity of the camera as a light reading instrument. I took 3 photos of the same scene, with a few seconds between each shot. Camera set to full auto, ISO 200 – though perhaps manual would have been better to fix the aperture and shutter speed (changed in picture 2) – I’ll need to reshoot and update. In the screen shots below there is a clear difference in the histogram for each image. Lesson is perhaps no two photos can be exactly the same, no matter how much control you think you have!
I also took 3 further pictures in lower light (shaded wood) and while the difference was less pronounced, there was still a difference. I guess that the lower the dynamic range in the scene, the less pronounced the difference in the images will be.