Exercise to: Take three or four exposures of the same scene. don’t change anything on the camera and keep the framing the the same.

The photos below are the result of this experiment:

shots taken in ‘P*’ Programme Mode, hand held at 9:00 pm – f/5.6, 1/125 sec, 50mm, ISO 4000

As expected each of the shots looks identical, but on taking them into Lightroom and cycling through them, I could see small changes in the histograms.  They don’t really show in the photos above but are noticeable when going from one to another.