Wednesday, August 29, 2012


Although there is little difference in the appearance of a dSLR camera and its 35mm film predecessor, that has to do with the human ergonomic way of using tools and obscures the fact digital photography has little in common with film photography.Yes both cameras use lenses and shutters and similar viewfinders, but the process is not alike even though both can produce photographic looking images.

The camera originated as a mechanical, optical-chemical device from the industrial revolution well over 100 years ago. Some of it’s first image making tasks were to record the movement of horses running and birds flying, and provided insights and understandings that began the modern machines of transportation we now have with railroads, automobiles and airplanes. But the cameras and the pictures they reproduced were physical objects made by a machine process of exposing light sensitive silver to the light reflected through a lens onto film. And the process of development was a physical change to the exposed silver by chemical reaction, producing an object and product of a machine, a thing that is a physical photographic image we know as a transparency, negative and print.

For the sake of mutual understanding let’s assume all subjects are a part of nature reflecting light that can be focused onto a light sensitive medium, either photo film or a digital camera sensor chip. Even though the subject may include artificial man-made objects like an automobile, a bicycle, or a house, they are all manufactured from natural ingredients, so they are really as natural as grass, trees, water, air and people.

The one key difference that distinguishes digital from the old mechanical method of producing a photo image of reality is that it is now done with electricity. Another distinction is that the digital area array senor is actually a matrix of pixels or sensor sites which applies its form to the reflected light of a subject. The result is the exposure is a measurement of millions of independent matrix elements which defines a metrical pattern. So what is reproduced is a representation of light measurement reading that fit into a matrix form and the electricity generated by this measurement is recorded as number values of different amounts of red, green and blue values. In other words a metrical collection of numbers recorded as a file that if read with an editor would not reveal a picture. Just pages of rows and rows of numbers and a few letters.

A digital photo only looks like a picture when opened with a photo application and the RGB pixel values are displayed as pixel colors in an LCD display. A personal computer has no idea of what a user is seeing on screen. LCD display adjustment, calibration and profiling will help match the screen image to what is printed using a color managed application like versions of Photoshop. But still the adjustment of image values is mechanical using basically the same mechanical adjustment tools first offered in computer paint programs in the 1980’s - nothing has changed basically just refinements. However there are exceptions in software that does recognize the matrix pattern of image content by a computer. First of all cameras and some photo applications have borrowed surveillance face recognition technology. The Professional Portrait retouching application also recognizes digital camera matrix patterns to automatically retouch face pictures made with digital cameras. And of course the system of automatic image adjustment editing recently released to individual users as Organic Imaging functions on the basis of a massive library of digital images they have recorded and processed over the last decade.

Otherwise the typical personal computer is blind to the information it processes when the content is digital camera made files. The main processor is device independent from the display - there is no personal computer recognition of digital images by either the computer or the display, which is only there to provide a GUI feedback and control of what the computer’s applications are processing. An adjustment of displayed digital photographic qualities has to be evaluated by user’s perception and adjusted by sight and individual judgment. The hardware and software are potentially capable of digital matrix pattern recognition and automated adjustment, but the companies that design, make and sell personal computers so far have not even acknowledged that digital image recognition and automated adjustment based on image recognition is possible or of any interest to users. So don’t expect a new model personal computer that is digital photo image aware  and capable of automated digital image adjustment any time soon. What we are getting is a slicker package design with faster and faster CPU chips, but basically the same design capabilities that were available in 1990.

Of course I must add that scanning film images produces a digital photo file that is electrically generated and a hybrid version of digital photographs. This fact allows the editing of these images advantages of both the film and digital mediums. But unfortunately matrix pattern sensitive automated function like retouching do not work the same to support automatic retouching as effectively as it can be done with digital camera produced portraits. However, the Organic Imaging ( application and process seems to automatically adjust scanned film images as effectively as digital camera made photographs.

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