This set of pictures shows stepping through different focal lengths using a fixed aperture and a fixed spot. The camera was tripod mounted both for consistency of image and because being a dull day at f22 demanded a slow speed of 1/5 second.
I stepped through 3 lenses for the shots using focal lengths of 16mm to 135mm on a camera with a crop factor of 1.5.
Two issues I faced were:
- Firstly the time between shots was a good couple of minutes as people kept walking through the colonnade, but being a dull day the consistency of the light did not affect the final image.
- Secondly I started from a wide angle and constantly zoomed in. When I got to the final image I found that I was very much off where I thought the centre should be. Therefore the images were taken in reverse order so as to have a known centre spot and work backwards.
My opinion is that the 28mm represents roughly normal vision. It seemed like my ‘real view’ when standing there.
The final images were JPEGS output in Lightroom from RAW files. No upright or horizontal correction was used to ensure any distortion caused by the wide angle or telephoto remains in the image.
In these two images I have taken the detail from the far end of the colonnade. The first is from the 18mm shot and the second from the 135mm. While the first is a little more grainier/noisier because of the enlargement required it can be seen that even through using differing focal lengths the perspective geometry remains the same.