County, King, 200411, King County 2002 Color Aerial Photography: King County, King County, WA.
This is a Raster data set. It contains the following raster data types:
Planar coordinates are encoded using Row and column
Planar coordinates are specified in Feet
The horizontal datum used is North American Datum of 1983, 1991 correction.
The ellipsoid used is GRS 80.
The semi-major axis of the ellipsoid used is 20925604.4720406.
The flattening of the ellipsoid used is 1/298.26.
The 2002 King County orthorectified color imagery updates the King County Spatial Data Warehouse. Data is available for a range of internal and external GIS, engineering and other mapping applications. This data replaces Version 1 of the 2002 King County data which was stored in a lower-resolution format. The King County data provides full-county coverage.
A thorough horizontal accuracy check has not been performed on the dataset.
For the 1" = 1700' source photos: Maximum error, in areas of strong relief or over elevated features (i.e, overpasses), may be as great as 15 feet. Generally, error is expected to be less than this, in the range of 6-10 feet.
For the 1" = 2500" source photos: Maximum error, in areas of strong relief or over elevated features (i.e, overpasses), may be as great as 20 feet. Generally, error is expected to be less than this, in the range of 10-15 feet.
The dataset includes all images captured as part of the overflight. There were 793 photos
collected for the 'western' (lowland) portion of the project area at a photo scale of
1" = 1700', covering an area of approximately 1500 sq. miles.
For the 'eastern' (upland) portion of the project area 306 photos where taken at a photo scale of 1" = 2500', covering an area of approximately 825 sq. miles.
Township tiles created from the 1" = 2500 foot photography are:
Townships 19 Ranges 09-12, Townships 20 Ranges 09-12, Townships 21 Ranges 09-12 Townships 22 Ranges 10-11, Townships 23 Ranges 10-12, Townships 24 Ranges 10-14 Townships 25 Ranges 10-13, Townships 26 Ranges 10-13
All other township tiles were created from the 1" = 1700' photography.
The three half-townships in eastern King County are incorporated into their adjacent full townships, T24R11, T24R12, T24R13, per the tiling scheme.
Variation in acquisition parameters, protracted acquisition schedule and water features result in less than optimal tonal balancing and overall color consistency. Adjustments to display characteristics in viewing software can enhance display quality.
Are there legal restrictions on access or use of the data?
- Access_Constraints: None
- King County digital data may not be reproduced or redistributed in any form or by any means without the express written authorization of the King County Department of Natural Resources and Parks/KCGIS Center.
tXXrYY_02n100.sid, where tXX refers to the PLSS township on which the tile scheme is based and rYY indicates the range. _02 indicates the acquisition year is 2002, 'n' indicates natural color orthophotography, with '100' representing 100/100ths foot (= 1 ft) ground sample distance resolutions (gsd). Tiling levels at 7500, township-range and zone are all stored at 1 foot pixel resolution (with required compression). The KeyRegion full-county mosaic is provided as resampled 1.5 foot pixels. This resampling was required to accomodate maximum compression limits.
King County disclaims any warranty of use of any digital product or data beyond that for which it was designed.