Week 2 Day 2

GIS by Hand

Materials: sheet protectors, sharpie, aerial photo, graticule
Instructions: trace out registration marks on both transparencies, trace polygon on one, line on other
Talk about tables of data and coordinate systems long and lat
Record data in table

Notes

GIS as drawing plus database with "geo referencing"
Each "feature" (which can be point, line/polyline, polygon/area) has spatial or geo data (the longitude and latitude of its vertices) and attribute data (what kind of a feature is it - building, tree, street, homicide — and various bits of data associated with that kind of feature).

1. Take note of registration marks on this aerial photo from FieldPapers. Place it under a piece of transparent plastic and use a pen to trace each of these marks onto the transparency. Repeat for a second transparency.

2. With the photo aligned to the registration marks trace out a few polygon features on the first transparency. Then repeat with the second transparency.
3. For each transparency, fill out a table like the one below for 2 or three objects on each sheet

ID Feature Type GeoInfo
1 polygon 1.2,3.2,4.2,4.5,2.3,2.7,4.5,2.1
2 polygon 2.0,3.0,2.0,4.0,4.0,3.0

4. Make up some attribute data for each feature.
5. Make up some display data for each feature. We should end up with something like this:

ID Feature Type GeoInfo Feature Name Fill Line
1 polygon 1.2,3.2,4.2,4.5,2.3,2.7,4.5,2.1 building Library yellow grey
2 polygon 2.0,3.0,2.0,4.0,4.0,3.0 parking lot P15 grey black