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NPR – what it isn’t

This is a re-post of parts of a talk I held at fmx/07 , together with Oliver Deussen from the University of Konstanz.

There is much frustration at the term “non-photorealism”. Something which defines itself as the negative of another thing is side-stepping an identification, of course – but more difficulty arises from the presumed assumption that we know what photorealism is. A director requesting “photorealism” as a visual style from a cameraman would rightly be scoffed at, yet cg artists are often confronted with exactly this definition of a desired style.

Photorealism isn’t a style.

nprnot_joseph-nicephore-niepce

The photo is a projected image captured when light falls on a light-sensitive surface. Initially, this process took place chemically, such as in the heliograph above – taken in 1826 by Joseph Nicephore Niepce. It could be considered the first photograph, certainly its the first permanent photograph. Earlier images had been created using photographic processes but they vanished after a short time.

The photoreal takes its reference from the physical properties of light as it finds its way through a focusing lens or pinhole and onto the flat plane of a photographic surface. As the image above shows, photoreal doesn’t necessarily refer to a crisp, focused representation of an existent scene…  it includes all effects and artifacts arising from the physical  properties of light and the chemical processes involved, as guided and manipulated by the photographer. Computer graphics has pursued rendering the photoreal within the limits of computational power and understanding of the processes.

In contrast, the non-photoreal takes as its reference the interaction between artist and material. At first glimpse, that says pretty much nothing.  But its a solid point of departure to better define what it is that NPR research strives to achieve.

nprnot_author

The intention of the photographer or the cameraman is to ‘capture’ existing objects – of course, both these objects and the photographic toolkit are both manipulated to achieve the desired visual and emotional impact. He/she is concerned with subject matter, composition, lighting and the camera’s position and viewing angle, focus, etc.

The artist is also interested in these things, but – to a much greater degree than the photographer – the artist is concerned with technique - the interplay of tool and material at the hand of the artist. Tools and materials are expected to influence or even guide the creation of an artwork.

materiality; the photographer looks, the artist listens

nprnot_woodcut

The grain of a tree stem suggests form to the sculptor, the grain of a woodcarving leaves its signature in ink as it is pressed against paper. It is a sign of authenticity that the artist listens to materials. As the sculptures below illustrate, one material can suggest endless possible forms and techniques, and the work lives from the tension between this material and its development.

13_influence

two eyes are more than one

I see a further distinction in the multiplicity of perspective: looking through the camera means reducing one’s vision to one point in space. Artists can also pursue this singular perspective, but more often than not, they are in some form juggling multiple perspective. The extreme can be seen in cubism.

temporal concerns: it’s about time

A last distinction: only seldom does photography span longer frames of time… such as cameras set to capture sprinters as they cross the goal line. Most often, the photographer – even the cameraman – is intent on a fraction of time measured in f-stops. Even time-lapse photography consists of consistent segments of time. The artist is constantly confronted with temporal incongruities, for the simple fact that the process of formulating an image spans a longer period of time.

More about these distinctions in future posts…
next: NPR _ materials in the void

There are 1 Comments to this article

drip | david’s really interesting pages… says:
02/26/2009

[...] Previously, I proposed that a major distinction between NPR and ‘realistic’ rendering is intention in dealing with the tools and materials involved. But what is material within the immaterial working space of computer graphics? And can the artistic sense of authenticity play a role in computer graphics? Can any one produced visual be considered more authentic than another? [...]

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