1. Scan in maps with HP 4C scanner and save as TIF file
2. Bring TIF file into ARC/INFO
3. Register image to NCTGIS street centerline file
4. Convert image from TIF to GRID (ArcInfo raster format)
5. Convert GRID to Arcs (this improves processing speed)
6. Bring polylines into ArcView

 

** The above procedure accurately (or as closely as possible) and permanently places the image over the street centerline file. **

 

7. With NCTGIS file and image open, bring in 1990 TIGER tract for Dallas area

 

** We use the 1990 TIGER tracts because they have the polygons we need (they're just not shaped entirely accurately) and we won't have to draw them all in again.**

 

8. use the "select-by-theme" to select 1990 polygons which intersect with the 1940 poly lines, and save as shape file.

**This step eliminates those polygons from 1990 that did not exist in 1940 and provides us with inaccurately placed 1940 census tract polygons

9. use dissolve process to combine 1990 split polygons by removing internal lines.

 

10. Handy edit tools:

Our goal is to adjust the polygons , using the scanned image and NCTGIS street centerline file as guides.