This page updated: February, 2011

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Technical Instructions

Part 2

Specifications

Standards for Digital Elevation Models

U.S. Department of the Interior

U.S. Geological Survey

National Mapping Division

Part 2: Specifications

Appendix 2-G

(00) Geographic [Parameter]

(01) Universal Transverse Mercator (UTM Zone)

(02) State Plane (Zone)

(03) Albers Conical Equal Area .. (04) Lambert Conformal

[1]Semimajor axis of ellipsoid. If this field is left blank (=0), the value for Clarke's 1866 spheroid in meters is assumed.

[2]Eccentricity squared of ellipsoid (e^2). If field is zero, this indicates a sphere. If the field is 1, this field is interpreted as containing the semiminor axis of the ellipsoid.

[3]Latitude of 1st Standard Parallel

[4]Latitude of 2d Standard Parallel

[5]Longitude of Central Meridian

[6]Latitude of projection's origin

[7]False easting in the same units of measure as the semimajor axis of ellipsoid

[8]False northing in the same units of measure as the semimajor axis of ellipsoid

[9..15]NA

(05) Mercator

(06) Polar Stereographic

(07) Polyconic

(08)Equidistant Conic {Type A} {Type B}

[1] Semimajor axis of ellipsoid. If this field is left blank (=0), the value for Clarke's 1866 spheroid in meters is assumed.

[2] Eccentricity squared of ellipsoid (e). If this is left blank (=0), this will indicate a sphere. If the field is 1, this field will be interpreted as containing the semiminor axis of the ellipsoid.

[3](08){A}Latitude of Standard Parallel

(08){B}Latitude of 1st Standard Parallel

[4](08){B} Latitude of 2d Standard Parallel

[5] (05..07..08)Longitude of Central Meridian

(06)Longitude directed straight down below pole of map

[6](06)Latitude of true scale

(07..08)Latitude of projection's origin

[7](05..06..07..08) False easting in the same units of measure as the semimajor axis of ellipsoid

[8](05..06..07..08)False northing in the same units of measure as the semimajor axis of ellipsoid

[9](08){A}Zero {B}Any nonzero number

[10..15]NA

(09) Transverse Mercator

(10) Stereographic

(11) Lambert Azimuthal Equal-Area

(12) Azimuthal Equidistant

(13) Gnomonic

(14) Orthographic

[1](09) Semimajor axis of ellipsoid. If this field is left blank (=0), the value for Clarke's 1866 spheroid in meters is assumed.

(10..11..12..13..14)

Radius of the sphere of reference. If this field is left blank, the value 6370997.0 meters is assumed.

[2](09)Eccentricity squared of ellipsoid (e^2). If field is zero, this indicates a sphere. If the field is 1, this field is interpreted as containing the semiminor axis of the ellipsoid.

[3](09)Scale factor at Central Meridian

[4]{NA}

[5](09)Longitude of Central Meridian

(10..11..12..13..14)Longitude of center of projection

[6](09)Latitude of origin

(10..11..12..13..14)Latitude of center of projection

[7] False easting in the same units of measure as the semimajor axis or radius of the sphere

[8] False northing in the same units of measure as the semimajor axis or radius of the sphere

[9..15]NA

(15) General Vertical Near-Side Perspective

(16) Sinusoidal (Plate Caree)

(17) Equirectangular

(18) Miller Cylindrical

(19) Van Der Grinten I

[1](ALL)Radius of the sphere of reference. If this field is left blank, the value 6370997.0 meters is assumed.

[2] NA

[3](15)Height of perspective point above sphere

[4] NA

[5](15) Longitude of center of projection

(16..17..18..19)Longitude of Central Meridian

[6](15) Latitude of center of projection

[7](ALL)False easting in the same units of measure as radius of the sphere

[8](ALL)False northing in the same units of measure as radius of the sphere

[9-15]NA

(20)Oblique Mercator {Type A} {Type B}

[1] Same as for projections 03 thru 09

2 Same as for projections 03 thru 09

3 Scale factor at the center of projection

[4]{B}Angle of azimuth east of north for central line of projection

[5]{B}Longitude of point along central line of projection at which angle of azimuth is measured

[6]{A}Latitude of origin of projection

[7]{A}Same as for projections 03 thru 19

[8]{A}Same as for projections 03 thru 19

[9]{A}Longitude of first point defining central geodetic line of projection

[10]{A}Latitude of first point defining central geodetic line of projection

[11]{A}Longitude of second point defining central geodetic line of projection

[12]{A}Latitude of second point defining central geodetic line of projection

[13]{A}Zero{B}Any Non Zero Number: 1

[14..15]NA

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