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James Turk 2024-11-13 17:50:20 -06:00
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@ -9,6 +9,10 @@ Establish a baseline understanding of GIS data.
(Not focused on Data Viz)
### Next
Browser Mapping Libraries
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## GIS Fundamentals
@ -132,17 +136,20 @@ PCS is not so uniform, but most common is the **UTM** is the Transverse Mercator
Localities will often publish in a more local projections:
SPCS - State Plane Coordinate System, actually 125 zones with their own system across US. They are fine-tuned to fit the shape of each state to maximize accuracy. (Some use transverse Mercator, some use a Lambert conformal conic projection, all with different parameters.
SPCS - State Plane Coordinate System, actually 125 zones with their own system across US. They are fine-tuned to fit the shape of each state to maximize accuracy. (Some use transverse Mercator, some use a Lambert conformal conic projection, all with different parameters.)
![bg right](a3585f84-8cf4-451c-b079-0bb2ac338c6d.jpg)
(ce: conservation.ca.gov)
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## rm *.prj
## Correct Projection is Essential
In practice, it is **essential** that you know what CRS your data is in and what CRS you are displaying it in.
Failure to do so leads to incorrect results, heavily distorted maps, and real-world trouble.
Failure leads to incorrect results, heavily distorted visualizations, and real-world trouble.
![bg left fit](bad-proj.jpg)
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