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Frank Gerlach 
  
4. Product Descriptions 
Product Availability as of March 28,2000, Space Imaging has released the following CARTERRA products based on 
IKONOS imagery, described below. 
1) CARTERRA™ Geo Pan and Multispectral 11 bit 
2) CARTERRA ™ Reference Pan 11 bit 
3) CARTERRA ™ Precision Pan 11 bit 
4) CARTERRA ™ Precision Plus Pan 11 bit, only as a non-standard quote with customer supplied DEMs 
Products are delivered as 11-bit black-and-white and 11-bit color images. 11-bit imagery corresponds to 2048 shades of 
gray per pixel, compared to 256 shades of gray per pixel in traditional 8-bit imagery. The value of 11 bit data for customers 
is that it has a richer dynamic range, providing an enhanced ability to distinguish detail in shadows and brightly lit areas. 
Future product releases will include Pan Sharpened imagery. These products will consist of 1 meter natural color and false 
color imagery for various products such as Geo, Reference and Precision. The IKONOS satellite can produce digital 
elevation models from stereo images. The corresponding Carterra DEM product has not yet been released. The proposed 
DEM has a post spacing of one arc-second and a vertical accuracy requirement of 12m LE90. 
4.1 Product Options 
Format - GeoTIFF and NITF 2.0 
Projections — UTM, State Plane, Albers Conical Equal Area, and Lambert Conformal Conic 
Datum / Ellipsoid - WGS 84, NAD 83 / GRS 1980, Tokyo, and NAD 27 
Media - CD-ROM and 8 mm tape 
42 CARTERRA Geo 
On January 3, 2000, Space Imaging introduced CARTERRA Geo ™ , high-resolution, geo-corrected imagery collected by 
IKONOS. CARTERRA Geo is ideal for projects not requiring a high degree of positional accuracy but which require quick 
delivery. Carterra Geo products are georectified and map projected. No terrain model is used so these images are not 
orthorectified. These images are collected with elevation angles as low as 50° (to permit rapid revisit), so terrain 
displacement can be significant. Accuracy of the Carterra Geo products is specified as 50m CE90 exclusive of terrain 
displacement. This accuracy was primarily tested operationally using relatively flat well-known terrain, so that terrain 
displacement is not an issue. On-orbit test results are consistently better than the product accuracy specification of 50m 
CE90 exclusive of terrain displacement. 
4.3 CARTERRA Reference 
Carterra Reference products are ideally suited for applications where quick delivery and less positional accuracy is crucial, 
including large-area or regional mapping, GIS backdrops, real estate planning, change monitoring, agricultural monitoring, 
site evaluation, insurance assessments, natural disaster assessments, media reporting and other applications. Carterra 
Reference products are orthorectified to a terrain model. The collection elevation angle can be as low as 60° depending on 
the accuracy of the available terrain model. The 60° elevation angle constraint reduces building lean and other 
orthorectification artifacts. The accuracy of Carterra Reference products was tested on-orbit. A terrain model of the 
Coterminous US (CONUS) was used. Test results are consistently better than the 25m Carterra Reference product accuracy 
specification. 
44 CARTERRA Precision 
Carterra Precision products are designed for provincial, state and local government projects, as well as transportation, 
utilities, telecommunications, real estate and other traditional geographic applications. These products are ideally suited for 
applications requiring a high degree of positional accuracy, such as base mapping, cadastral mapping, city planning, 
geographic information system (GIS) updates, change management, site selection and development. Carterra Precision 
products are orthorectified with a terrain model and ground control. Carterra precision products are specified to have an 
accuracy of 4m CE90, satisfying National Map Accuracy Standards for 1:4800 mapping. To reduce terrain displacement, 
the image acquisition elevation angle is higher than for Carterra Reference. This further reduces building lean and other 
orthorectification artifacts. Operational tests show it to be satisfying the 4m CE90 product specification. 
  
International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part Bl. Amsterdam 2000. 135