Preservation/Distortion
Where is distortion greatest on a polyconic projection?
Towards the edges of the map
What common developable surface is used to create this projection
Conic
Would this map be used in Ghana
Yes
What regions/area would this projection be best used for
Primarily for regions with a predominant north/south extent. Ex: United states
Where did Lesley visit on her honeymoon
The Greenwich meridian
Where is there zero distortion on a polyconic projection
On the central meridian
How many cones are used to create the projection?
infinite
Would this map be used for New Zealand
No
Would a polyconic projection be good for making maps of small areas
Yes, due to it using multiple cones to reduce distortion over small areas, allowing a high level of detail and accuracy
If a polyconic map were a person, who would it be: a perfectionist who insists on preserving one property perfectly, a diplomat who tries to keep everyone equally happy, a specialist who only works well in certain areas
Assuming mercator is a perfectionist, polyconic would be a diplomat as it was practical and not flashy
Is north/south or east/west distortion greater
East/West
What aspect is used in the projection shown
Normal, north/south oriented
Would you want to use this map to travel between UK and Algeria
yes you could, because its along the central meridian direction is preserved.
Why was the polyconic projection widely used in the U.S. before modern GIS projection became common
Because it handles irregularly shaped regions better, making it practical for state-by-state topographic surveys
Is Lesley a certified Alberta Land Surveyor
Yes, she was the 11th woman in Alberta to be commissioned as an ALS
What properties does a polyconic projection preserve/distort
It does not preserve area or shape as it is a compromise projection, so it tries to reduce distortion as much as possible to make the map "look right"
How does a polyconic projection differ from a conic projection
The meridians are curved aside from the central meridian
Would you want to use this map to travel from Alaska to France
No
How does the polyconic projection compare to projections like mercator or transverse mercator for large scale surveys
Very good accuracy along the central meridian, minimal scale distortion for moderately sized regions, worked well for topo before modern computers.
Not conformal, distortion grows going in east/west directions, not good for global coverage.
What year did Lesley write about diversity in surveying
2006