Penn State Data Commons - Full Metadata

Abstract:

Historic USGS 15 minute topographic maps for Pennsylvania as collected from the MapTech Historical Map Collection at 'http://historical.maptech.com'.  Scanned map images from MapTech were downloaded, assembled, and registered and rectified via Arc/Info to the UTM Zone 17/18 NAD83 projection.

Purpose:

These USGS 15 minute images, derived from the MapTech historical collection, are for historical purposes only. Users are encouraged to visit the MapTech site, and acknowledge the volunteers who orginially scanned and compiled the collection.

Supplemental_Information:

The United States Geological Survey was established on March 3, 1879 and began its topographic atlas of the United States in 1882. The oldest Pennsylvania maps in the online MapTech collection date from the 1890's. The online collection for Pennsylvania comprises over 330 USGS topographic maps.  Overall, the MapTech site includes complete geographical coverage of New England, New York, Pennsylvania, New Jersey, Delaware and Maryland from the 1890s to 1950s. It is slowly being expanded as time permits, through volunteer efforts.

Currentness_Reference:

publication date

Use_Constraints:

For historical purposes only.

Data_Set_Credit:

Historian Christopher Marshall and others who scanned and compiled the collection, MapTech for hosting the collection online, and PASDA for combining and registering the images for GIS use.

Attribute_Accuracy_Report:

USGS digital raster graphics (DRG's) normally use a standard palette to ensure uniform color throughout a particular map series.  This is to ensure that a particular color will remain consistent thoughout a DRG series.  For these raster images derived from the MapTech Historical collection at http://historical.maptech.com, there is no guarantee given for consistent colors.  This is due to the fact that images downloaded from the collection as jpegs had a 16 million color resolution, and after being combined, were reduced by an optimal best match method to 256 color (8 bit) depth.

Logical_Consistency_Report:

Great care was taken by eye to seam together the four separate jpeg images that were scanned for each topographic map at library sites.  Because of small levels of inaccuracy due to image rotation or scanner operation, there are varying amounts of error at seams where the images line up.  As other methods of lining up images automatically through software become available, some of these historical map images may be redone and replaced.

Source_Contribution:

Maps scanned at library sites to produce digital images.

Process_Description:

Scanned USGS 15 minute quadrangle jpeg images were downloaded from the MapTech Historical Map Collection website (http://historical.maptech.com).  Each full map had previously been scanned into four separate images at a library site.  The jpeg images were then carefully assembled into whole map images through the use of Paint Shop Pro software.  The whole map jpeg images were then converted to tiff images and reduced in color resolution to 256 colors.  Finally, using Arc/Info software, the tiff images were registered and rectified to UTM Zone 17 or 18, NAD 83.

Process_Description:

Metadata imported.

Attribute_Definition:

Internal feature number.

Attribute_Definition_Source:

ESRI

Address:

Land and Water Building

Distribution_Liability:

The USER shall indemnify, save harmless, and, if requested, defend those parties involved with the development and distribution of this data, their officers, agents, and employees from and against any suits, claims, or actions for injury, death, or property damage arising out of the use of or any defect in the FILES or any accompanying documentation. Those parties involved with the development and distribution excluded any and all implied warranties, including warranties or merchantability and fitness for a particular purpose and makes no warranty or representation, either express or implied, with respect to the FILES or accompanying documentation, including its quality, performance, merchantability, or fitness for a particular purpose. The FILES and documentation are provided "as is" and the USER assumes the entire risk as to its quality and performance. Those parties involved with the development and distribution of this data will not be liable for any direct, indirect, special, incidental, or consequential damages arising out of the use or inability to use the FILES or any accompanying documentation.

Address:

10 Industrial Way

Through a connection established by Maptech employee Ed Lecuyer, Chris Marshall approached Maptech to host the MapTech Historical Map collection.  Other contributors include Stephen Titchenal and Derrick Brashear. If you would like to help expand this collection, contact Chris Marshall through Maptech's e-mail address: sales@maptech.com.

Address:

Land and Water Building

Full Metadata

Historical 15 minute series USGS Map Collection for Pennsylvania