This past Sunday I took the ferry over to Wards Island to take a few photos. One of my targets for the day was to capture the feeling of motion. Being of a scientific bent of mind. I asked myself the question: What gives a static photograph the impression of motion? As I am wont to do I will attempt to answer my own question by breaking down and classifying motion in photos into two classes. These two classes are not exclusive both could be combined in single photo. More of Sunday's pictures.
The first class is those photographs that show motion by having motion blur. While a normal photograph is a frozen moment in time. This type of photo has frozen not a single moment but several moments. The photo on the left is the first of my pinhole lens shots that I really like! It was taken at ISO 200 and with a 15 second exposure, it was also very windy so the bushs and tree branches were also in motion. I had to saturate the colors to make the path of the two bicyclists visible. I have subclassed this as a linear motion blur. Another example of linear blur is when the camera is panned to follow a high speed object such as a race car, in this case the race car is fixed in focus while the background has a linear blur.
The photo on the right was taken in a heavy gust of wind with my lens stopped right down to maximum and at ISO 100 for a 2 second exposure. This subclass of motion blur for lack of a better name I will call cyclic motion blur. Cyclic because the object when disturbed oscillates around its at rest point. For an instance at both extents of its travel it stops moving giving it the characteristic of a multiple exposure stop motion strobe effect.
The next class I call perceptual motion. Our brain is hardwired through genetics and through life's teachings that nature has laws; gravity pulls down an object, if an object is past it's center of gravity it will fall over, water can't be put in a pile... We know without thinking that the shirts in the picture are not static but are being blown by the wind. It is not in the nature of a shirt to hang in the way that the photo shows unless there is wind.
Our mind tells us these people are running not standing still. If they were standing still they would be falling over.
This last example of the cyclic motion blur subclass was of an CNE ride at night.