Record Details
Bonneville Dam: 1939 Aerial Photographs: Guide Map
Oregon Digital
| Field | Value |
|---|---|
| Identifier | ORU_WMAP_001guide http://oregondigital.org/u?/wwdl,188 |
| Title | Bonneville Dam: 1939 Aerial Photographs: Guide Map |
| Description | Map showing position of available aerial photographs of the Bonneville Dam area taken in 1939 as part of the OCSW (determine acronym please!.) railroad survey. Contemporary terrain, major roads, populated places, and the Columbia River are shown as points of comparison. |
| Creator | Zaleski, Sarah Catherine |
| Date | 2004-06-23 2004-06-23 |
| Publisher | University of Oregon Libraries |
| Rights | (c) University of Oregon. This image is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 United States License (http://creativecommons.org/licenses/by-nc-nd/3.0/us/ ). Acknowledgement of the University of Oregon Libraries as a source is required. |
| Relation | University of Oregon Libraries - Document Center - Map & Aerial Photography Collection |
| Language | English |
| Type | image |
| Format | 4,137,604 bytes 24 bit -- RGB -- Untagged A base map of the subject area was created from readily available geospatial data repositories using ESRI ArcMap 8.3. The source layers include: a 1:250000 State of Oregon Digital Elevation Model, relevant USGS 1:250000 DEMs, a shapefile layer of Oregon towns, and 2 shapefile layers showing roads in Oregon and Washington. URLs for each source layer are in the Source field above. Aerial photographs were opened in Photoshop 6.0.1, cropped to remove borders, and saved as uncompressed TIFFs. Photos were then imported into ArcMap 8.3 and georeferenced using Vancouver E145122, a 1:24000 DRG composited from multiple USGS 7.5' quadrangles, as a reference. Georeferencing was performed using a minimum of 12 reference points, visually matched to the DRG baselayer. Each of the 3 aerial photos was added to the basemap, displayed using 254 levels of gray. The background color was set to 255 and displayed at no color. Black lines were manually drawn around the visible border of each photo. Yellow dotted lines were drawn around the hidden border of each photo. The resulting map and custom legend was exported from ArcMap as a 96dpi JPG file. |
