Orthomorphic projection
Also called: True-shape projection, Conformal projection · Topic: Map Projections · NCERT: Class 11, Ch 4 "Map Projections"
Meaning
An orthomorphic projection, also called a true-shape or conformal projection, keeps the correct shape of small areas. It does this by keeping the scale equal in all directions at each point. If land is stretched east-west at a point, it is stretched north-south by exactly the same amount. The cost is area. Regions far from the centre, or near the poles, look far bigger than they really are.
Example
Mercator's projection (1569) is orthomorphic. On it, Greenland (about 2.2 million sq km) looks about as big as Africa (about 30 million sq km), even though its small coastlines keep their true shape.
Don't confuse with
- Equal area projection (homolographic): this keeps area, not shape. No single map can be both equal area and orthomorphic.
- Orthographic projection: this is named after where the light source sits (at infinity). It does not keep shapes true. The two names sound alike and are a common exam trap.