[ Classic Forms ]

This section provides a detailed analysis of three classic forms of Graphical Perspective; namely Central, Parallel, and Spherical Perspective(s). Noteworthy is that Central Perspective encompasses Linear and Curvilinear Perspective(s), and we include a detailed analysis of the sources and fundamental Perspective Phenomena of those categories.

We emphasise the representative goals/functions of the named perspective types. Ergo, we are dealing largely with the artistic creation of an optical illusion of space, and especially depth, by means of flat images.

However, it is essential to note that these types of perspective can sometimes be employed for viewing or matching/modelling spatial reality. Said varied goals/functions are very much in keeping with a central theme of our work on perspective, whereby it is identified as an expansive subject that influences many visual/modelling/representative processes and related outcomes.

It is well to remember that often we have several Perspective Categories operating simultaneously to produce a combined visual effect. Accordingly, and in each case, it is helpful to identify all evident Perspective Phenomena, whereby we can then understand how and why the spatial world appears as it does.

Optical Perspective

At the PRC, we deal with Visual Perspective or Optical/Technical Perspective (often referred to simply as perspective). As the name suggests, Visual Perspective (of the first type, or not overtly related to the human visual system) refers to when a Visual Image is used to view, match or represent the visual appearance of a dimensional object/scene.

We are primarily concerned with one particular type of Visual Perspective, named Optical Perspective. We can define Optical Perspective, in general terms, as the process of picturing or representing a dimensional reality using optical methods (ref. physical, imagined, illusive reality, etc).

Optical Perspective is concerned with capturing, measuring, or representing realistic views of dimensional space (ref. may involve real, virtual or simulated light rays). Wherein a dimensional scene/object is analysed/represented using optical techniques. Optical Perspective encompasses all forms of perspective that use, or purport to use, light, or electromagnetic radiation, to probe a dimensional scene; including all wavelength ranges from gamma rays, x-rays, visual spectrum, microwaves, radio, etc.

As we shall learn, there are many different categories of Optical Perspective. Still, all involve projective principles that reflect particular scene geometry aspects with varying degrees of visual realism or accuracy.

Technical Perspective

Optical Perspective can be separated into the Technical and Non-Technical categories of Perspective. Technical Perspective can be separated into distinct categories and sub-categories. Still, importantly all types of Technical Perspective are recognised by having a direct connection to human vision, environmental optics, and related visual processes/methods or associated instruments/machines.

Technical Perspective refers to any systematic process that produces a detailed visual image, measurement, representation, model or view, of a dimensional object or scene. Technical Perspective is formed using optically, mathematically, geometrically, or logically correct/known/consistent principles.

Technical Perspective includes all naturally occurring optical effects that can be classified under optics of the environment, including, for example, optics of the heavens (sun, moon, and stars etc), shadow projection, panoramic views from mountain tops, underwater optics, etc. Also classified under the heading of Technical Perspective is the vision of all animals, including human vision and birds, frogs, fish, insect eyes etc.

Forms of Perspective

Each type of Optical Perspective can be realised in a specific Perspective Form; whereby there may be a whole variety of different kinds of Perspective Forms possible for each Perspective Category or Sub-Category. A Perspective Form is a physical embodiment (or real-world example) of a particular Perspective Category/Sub-Category.

For example, Linear Perspective is a Sub-Category of Graphical Perspective. Still, it can manifest itself in a whole variety of different Perspective Forms, including in forms such as in a drawing, painting, computer-generated image, virtual reality, etc. Each instantiated Perspective Form may be significantly, or subtly, different from the other Forms; even for a notionally identical image/view of the same dimensional scene/object.

Normally, we recognise a particular Form of Perspective through the unique changes imbued (Perspective Components of visual transformation) to a specific set of Visual Features linked to a dimensional scene or object. For example, a perspective drawing will have an evident physical embodiment, possessing a particular set of Perspective Phenomena, and be created in a specific way (e.g. pen and ink drawing on paper).

A Perspective Form will be instantiated by means of a specific set of Perspective Methods as explained herein, and elsewhere on this site.

Categories of Graphical Perspective

This section provides a detailed analysis of three classic types of Graphical Perspective; namely Central, Parallel, and Spherical Perspective(s). 

Patently these forms are most often embodied in one or more types of Graphical Perspective, which explains why we have so categorised the same under this heading. Nevertheless, it is salient to ask why we have placed special emphasis on these particular types of perspective; especially given that there are many hundreds of other Perspective Categories, Sub-Categories and Forms that exist.

We have singled out these particular types of Graphical Perspective, and labelled them as ‘classic’ because these are the most commonly known embodiments of all the Perspective Sub-Categories; at least if we consider those image or representation types that are spoken of as ‘perspectival’ in one way or another.

Once again, here on this site, we adopt a comprehensive approach to perspective subject matter; including identification of the Visual (2nd type), Mathematical, Graphical, Instrument, Forced, and Media Perspective Categories. Nevertheless, we thought it essential to fully understand the classic types of Graphical Perspective, before going into detail on the other catagories of perspective.