Geometric Perspective: Define/sub-concepts
- Different shapes based on distance and altitude
- L-Linear perspective: Parallel lines tend to converge as distance increases- railroad tracks coming together in the distance.
- A-Apparent foreshortening: Object appears oval or narrow at a distance and low altitude- Lake appears small from the ground at a distance.
- V-Vertical position in the field: Objects or terrain features at greater distances appear higher on the horizon. - Formation of aircraft, furthest one appears higher than the closest one.
Retinal Image Size: (Define/sup-concepts)
- Used in distance estimation, a viewed object is perceived to be a certain size.
- K- Known size of objects: nearer the object, larger its retinal image.
- I- Increasing/decreasing size: increases in size, it is getting closer.
- T- Terrestrial association: Comparison of known sizes determines relative size and distance.
- O- Overlapping contours: an object partially concealed is behind the object concealing it.
Aerial perspective: (define/sub-concepts)
- Clarity and shadows are used as cues for estimating distance.
- F- fading colors or shades: colors appear to fade with distance.
- L- loss of detail or texture: sharpness and clarity is lost with distance.
- P- Position of light source: direction and size of shadow determines position.
Motion parallax: (define)
-Apparent, relative motion of stationary objects as viewed by a moving observer. - Most important.
What are the monocular cues?
(GRAM)
- Geometric perspective
- Retinal Image Size
- Aerial Perspective
- Motion Parallax
Linear perspective:
(Geometric perspective)
-Parallel lines tend to converge as distance increases i.e. railroad tracks.
Apparent foreshortening:
(Geometric Perspective)
-Object appears oval or narrow at a distance and low altitude. Lake appears small from the ground at a distance.
Vertical position in the field:
(Geometric perspective)
-Objects or terrain features at greater distances appear higher on the horizon. i.e. a formation of aircraft, furthest one appears higher on the horizon.
Known size of objects:
(Retinal image size)
-Nearer the object, larger its retinal image.
Increasing/decreasing size:
(Retinal image size)
-Increases in size, its getting closer.
Terrestrial association:
(Retinal image size)
-Comparison of known sizes determines relative size and distance.
Overlapping contours:
(Retinal image size)
-An object partially concealed is behind the object concealing it.
Fading colors or shades:
(Aerial perspective)
-Colors appear to fade with distance.
Loss of detail or texture:
(Aerial perspective)
-Sharpness and clarity is lost with distance.
Position of light source:
(Aerial perspective)
-Direction and size of shadow determines position.
