Archived posting to the Leica Users Group, 2013/08/12
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]as a scientist, I was trained in physics, biology, and medicine.... sorry Larry, but I don't fully follow .... what do you think of this one? http://gallery.leica-users.org/v/barbour/paw2013/codyballs.jpg.html Steve On Aug 12, 2013, at 8:05 PM, lrzeitlin at aol.com wrote: > I'm glad that no winner has been declared in the Motion contest. Years of > being an art critic for several local newspapers have convinced me that > image selection by a single juror is a fallible process. Some images and > photos that have been declared "Best of Show" by one juror have been > rejected by another. It's all a matter of personal taste, the Zeitgeist, > and for all I know, the phase of the moon. But I'd like to get something > off my chest without, hopefully, offending anyone. > > > About BLUR. It is well to remember that blur is an artifact of the > photographic process. I am appalled by some comments made during the > Motion contest that suggest that a depiction of blur automatically implies > movement. > > > Normally the human eye doesn't see blurring of a moving object. When we > look at something in motion our eyes alternate between quick eye movements > and focusing on a single point on the object. When our eyes are moving, we > are functionally blind. We see the moving object as a series of still > images which our brain fuses together into a concept of motion. When we > track a moving object by fixating on a single point the motion blur of the > object is eliminated. Instead the background itself becomes less clear. > > > To see what I mean, remember that the refresh rate of the normal human eye > is between 15 and 20 times a second. Early motion pictures used 16 frames > a second to depict motion. Now drive down the highway at 60 mph. (Try 100 > kph if you are mileage impaired.) The roadway seen out of the windshield > appears perfectly sharp. You can read the traffic signs, see the bumps in > the road, even the dead squirrel crushed by the previous car. Now point > your camera at the roadway and take a picture through the windshield at > 1/20 second. Everything I mentioned will be blurred. The foliage along the > edge of the road will no longer be sharp, Bumps and potholes will be > indistinct. And you will be unable to tell if the carcass on the road is a > squirrel or a cat. The camera doesn't have a brain. Hopefully you do. > > > Cameras traditionally recorded a moving object as blurred because older > films required a shutter speed which was insufficient to record the > details of the scene at a moment in time. In the early days of photography > exposure times were measured in minutes. Or the camera itself would shake > and everything in the frame is blurred. Over the years viewers of still > pictures learned that blurred images meant that the object shown was > moving. Interpreting a photograph is a learning process. There is little > in a photo that truly duplicates reality. ? > > > Most modern digital cameras incorporate camera motion detectors to > minimize the effects of camera shake. One part of the pre WW2 Leica/Contax > conflict was the argument about which direction of shutter movement, > vertical or horizontal, produced the most convincing representation of > object motion. Contax seemed to be the winner, at least in auto and bike > racing since the vertical motion of the shutter distorted wheels so they > appeared to be tilting forward. This implied rapid motion. Auto and bike > posters of the era were drawn to emphasize this effect. > > > Appropriate selection of shutter speed or following the motion of a moving > object can introduce enough controlled image blur to give the impression > of motion but you have to know what you are doing. BLUR DOES NOT > AUTOMATICALLY MEAN MOTION. Sometimes it just means bad photography. Motion > should be suggested by picture content. Not by exploiting a past > limitation of the photographic process. Remember that Harold Edgerton's > strobelight photos, the first that captured the motion of really high > speed objects like bullets cutting a playing card, were perfectly sharp. > > > In the 21st. century. it is well not to be bound by the limitations of the > past or the opinions of mossbacks like myself. > > > Larry Z > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information