Category Archives: 1: The instrument

Project 1: Exercise 1.1

Take 3 exposures from the same place without moving or changing the settings on the camera. Then look closely to examine for any differences and look closely at the histogram.

I deliberately chose a shaded spot in the garden when there was a cloudy sky and minimal wind to minimise external variations. The camera was set to program and the aperture, shutter speed and ISO remained constant (1/100 sec, f/4.7, ISO320). Capture time 03/04/17 at 12:11:13, 12:11:14 and12:11:16.

On visual inspection, even when enlarged to 3:1 I could not see any difference between the images, however on looking closely at the histograms there was a slight shift.

  • The luminosity increased slightly over the 3 images, the median shifting from 125 to 126 to128
  • The colours shifted from a marginal preponderance of blue to a slight increase in red.

The changes are so small that they needed very close examination of the histogram to be visible, but are present.

Image 1Image 2Image 3