DATUM information, from Michigan DNR--quoted below.


What is a Reference System?
                   A map projection will transform, or alter, two angles (latitude and longitude) in three dimensions, to x
                   and y Cartesian coordinates in two dimensions.  How do we come up with the latitude and longitude for
                   a particular location?  We tend to think of latitudes and longitudes as absolutes, but they are not.  The
                   angles that we call latitude and longitude are based on measurements that are relative to a specified
                   origin and based on a model that has a precise shape and vertex.

                   Even in a simple two-dimensional case, trying to describe the location of a point with only an angular
                   distance is useless, unless we know the location of the angle’s vertex and the location of measurement.

                   A reference system is used to transform a physical location somewhere on earth to a specific latitude
                   and longitude.  A reference system, also referred to as a Datum, provides the necessary model of the
                   planet, the necessary origin points, and physical measurements to describe where a point of origin is
                   relative to other points of origin.

                   There are two reference systems commonly used in Michigan: the North American Datum of 1927
                   (NAD27), and the North American Datum of 1983 (NAD83).

                   The NAD83 system represents a readjustment and refinement of the NAD27 system, providing more
                   accuracy and better compatibility with satellite-based navigation systems. Because of this, the latitude
                   and longitude of any particular point specified with respect to the NAD27 system is not the same as the
                   latitude and longitude of the same point specified with respect to the NAD83 system.

                   Conversion tables and computer programs have been developed to translate between points based in
                   NAD27 and NAD83.



From the ArcView online help:

Datum

A datum is a set of parameters defining a coordinate system, and a set of control points whose geometric relationships are known, either through measurement or calculation (Dewhurst, 1990). A datum is defined by a spheroid, which approximates the shape of the Earth, and the spheroid’s position relative to the center of the Earth. There are many spheroids representing the shape of the Earth, and many more datums based upon them.

A horizontal datum provides a frame of reference for measuring locations on the surface of the Earth. It defines the origin and orientation of latitude and longitude lines. A local datum aligns its spheroid to closely fit the Earth’s surface in a particular area and its 'origin point' is located on the surface of the Earth. The coordinates of the 'origin point' are fixed and all other points are calculated from this control point. The coordinate system origin of a local datum is not at the center of the Earth. NAD27 and the European Datum of 1950 are local datums.

In the last fifteen years, satellite data has provided geodesists with new measurements to define the best Earth-fitting ellipsoid, which relates coordinates to the Earth’s center of mass. An Earth-centered, or geocentric, datum does not have an initial point of origin like a local datum. The Earth’s center of mass is, in a sense, the origin. The most recently developed and widely used datum is the World Geodetic System of 1984 (WGS84). It serves as the framework for supporting locational measurement worldwide. GPS measurements are based upon the WGS84 datum.



State Plane from ESRI

The State Plane Coordinate System is not a projection. It is a coordinate system that divides all fifty of the United States, Puerto Rico and the US Virgin Islands into over 120 numbered sections, referred to as zones. Depending on its size, each state is represented by anywhere from one to ten zones. The shape of the zone then determines which projection is most suitable. Three projections are used: the Lambert Conformal Conic for zones running east and west, the Transverse Mercator for zones running north and south, and the Oblique Mercator for one zone only, the panhandle of Alaska. Each zone has an assigned USGS code number, each having a designated central origin which is specified in degrees.

The State Plane Coordinate System was originally designed to use the North American Datum of 1927, or NAD27. It uses the Clarke spheroid  of 1866 to represent the shape of the earth. The origin of this datum is a point on the earth referred to as Meades Ranch in Kansas. Many NAD27 control points were calculated from observations taken in the 1800s. These calculations were done manually and in sections over many years. Therefore, errors varied from station to station. To use one of the State Plane projections in NAD27, select State Plane - 1927 from Projection Properties.

A new datum was developed in 1983, as technological advances in surveying and geodesy revealed weaknesses in NAD27’s control points. NAD83 uses the GRS80 spheroid, and is based upon both earth and satellite observations.  The origin for this datum is the earth’s center of mass. To use one of the State Plane projections in NAD83, select State Plane - 1983 from Projection Properties.
Method of projection    Projection may be cylindrical or conic. See Lambert, Transverse Mercator, and Oblique Mercator for methodology and properties.

Uses and applications
 Standard USGS 7 1/2- and 15-minute quad sheets.


STATE PLANE COORDINATE SYSTEM--MICHIGAN DNR QUOTED BELOW
(LAMBERT CONFORMAL CONIC PROJECTION)

What is the Michigan State Plane Coordinate System?
                   Each state is expected to designate a particular map projection scheme that both the federal
                   government and the state may use as a convention.  The federal government specified that these state
                   systems keep distortion within certain limits.  For example, a feature with a real length of 10,000 feet
                   should never appear to be shorter than 9,999 feet nor longer than 10,001 feet in the projected image, no
                   matter where in the state that feature appears.

                   Each state has one of these federally recognized systems.  Ohio's system is called Ohio State Plane;
                   Michigan's is called Michigan State Plane, etc.

                   Prior to 1964, Michigan relied on a system that was based on three vertical projection zones.  This
                   system was the result of the federal government's initiative, the State Plane Coordinate System of
                   1927.  This system, with it's vertically-oriented zones, created an unnecessarily large number of long
                   boundaries between zones, and subdivided both the Lower and Upper Peninsulas.

                   Today, Michigan achieves the specified limits in distortions by breaking the state into three separate
                   horizontally-oriented projections.  The entire Upper Peninsula makes up the northern zone, the northern
                   half of the Lower Peninsula is the central zone, and the southern half of the Lower Peninsula is the
                   southern zone.

                   There have been two iterations of this system.  The first was adopted by the Michigan Legislature in
                   1964.  Then in 1983, the federal government made broad revisions to the entire set of state systems and
                   published these revised standards as the State Plane Coordinate System of 1983.



Working with datums, from ArcView

A datum is a set of parameters defining a coordinate system, and a set of control points whose geometric relationships are known, either through measurement or calculation. One part of defining the coordinate system is the spheroid used to approximate the shape of the earth.
A spheroid is defined by a radius and an eccentricity. These two constants are used as inputs to the equations which calculate a projected coordinate from a coordinate in decimal degrees. When a projection is created, it is associated with a default spheroid so that these constants will be available. This default spheroid varies from projection to projection, but is usually the SPHERE for small-scale projections and CLARKE 1866 for large-scale projections.

Certain predefined projections (for example, those stored in default.prj in ArcView's etc directory which are displayed as "standard" projections in Projection Properties), are associated with specific spheroids based on their use. For instance, the "State Plane - 1927" projections are associated with the CLARKE 1866 spheroid (with the exception of Michigan), the "State Plane - 1983" projections are associated with the GRS 80 spheroid, the "New Zealand National Grid" projection is associated with the INTERNATIONAL 1909 (also known as the INTERNATIONAL 1924) spheroid, the "Great Britain National Grid" projection is associated with the AIRY spheroid, and the National Grids of Malaysia, Singapore, and Brunei are associated with the EVEREST spheroid.

When a projection associated with a certain spheroid is used, ArcView assumes that the decimal degrees data being projected was collected in a datum based on that spheroid. So while ArcView has no knowledge of datums per se, it does know about spheroids, which are part of the definition of a datum. Therefore you do need to know what datum your data is in, and set the spheroid of the projection accordingly. This can be done either through the Projection Properties dialog or by using Avenue.



Datum shift information from ArcView:

Areas of Use

On the Datum tab of Steps 2 and 3 of the wizard, you set which geographic transformation you want to use. These transformations can be used from the command line using the -IG and -OG options using the POSC codes.
 

Geographic Transformation Code Area of use

GEOTRANSFORMATION_UNSET -1 No datum shift will occur

AMERSFOORT_TO_WGS_1984 8012 Netherlands
ETRS_1989_TO_WGS_1984 8049 Europe
GDA_1994_TO_WGS_1984 8050 Australia
ED_1987_TO_WGS_1984_1 8137 North Sea south of 62 deg N

 (UK,Denmark,Germany,Norway) and
 Netherlands (offshore)

ED_1950_TO_ED_1987_2 8138 Norway (offshore north of 65 deg N)
WGS_1972_TO_WGS_1984_1 8140 World
WGS_1972_TO_WGS_1984_2 8141 World
AGD_1984_TO_WGS_1984_2 8139 Australia
ADINDAN_TO_WGS_1984_1 8000 Mean for Ethiopia and Sudan
ADINDAN_TO_WGS_1984_2 8001 Burkina Faso
ADINDAN_TO_WGS_1984_3 8002 Cameroon
ADINDAN_TO_WGS_1984_4 8003 Ethiopia
ADINDAN_TO_WGS_1984_5 8004 Mali
ADINDAN_TO_WGS_1984_6 8005 Senegal
ADINDAN_TO_WGS_1984_7 8006 Sudan
AFGOOYE_TO_WGS_1984 8007 Somalia

AGD_1966_TO_WGS_1984 8008 Australia
AGD_1984_TO_WGS_1984_1 8009 Australia
AIN_EL_ABD_TO_WGS_1984_1 8010 Bahrain
AIN_EL_ABD_TO_WGS_1984_2 8011 Saudi Arabia
ARC_1950_TO_WGS_1984_1 8013 Mean for Botswana, Malawi, Swaziland,

 Zaire, Zambia, and Zimbabwe

ARC_1950_TO_WGS_1984_2 8014 Botswana
ARC_1950_TO_WGS_1984_3 8015 Burundi
ARC_1950_TO_WGS_1984_4 8016 Lesotho
ARC_1950_TO_WGS_1984_5 8017 Malawi
ARC_1950_TO_WGS_1984_6 8018 Swaziland
ARC_1950_TO_WGS_1984_7 8019 Zaire
ARC_1950_TO_WGS_1984_8 8020 Zambia
ARC_1950_TO_WGS_1984_9 8021 Zimbabwe
ARC_1960_TO_WGS_1984 8022 Mean for Kenya and Tanzania
BATAVIA_TO_WGS_1984 8023 Indonesia (Sumatra)
BERMUDA_1957_TO_WGS_1984 8024 Bermuda
BOGOTA_TO_WGS_1984 8025 Columbia

BUKIT_RIMPAH_TO_WGS_1984 8026 Indonesia (Bangka and Belitung Islands
CAMPO_INCHAUSPE_TO_WGS_1984 8027 Argentina
CAPE_TO_WGS_1984_1 8028 South Africa
CAPE_TO_WGS_1984_2 8029 South Africa
CARTHAGE_TO_WGS_1984 8030 Tunisia
CHUA_TO_WGS_1984 8031 Paraguay
CORREGO_ALEGRE_TO_WGS_1984 8032 Brazil
ED_1950_TO_WGS_1984_1 8033 Mean for Austria, Belgium, Denmark,

 Finland, France, Germany (West),
 Gibraltar, Greece, Italy, Luxembourg,
 Netherlands, Norway, Spain, Sweden,
 Switzerland, and Portugal

ED_1950_TO_WGS_1984_2 8034 Mean for Austria, Denmark, France,

 Germany (West), Netherlands, and
 Switzerland

ED_1950_TO_WGS_1984_3 8035 Mean for Iraq, Israel, Jordan, Kuwait,

 Lebanon, Saudi Arabia, and Syria

ED_1950_TO_WGS_1984_4 8036 Cyprus
ED_1950_TO_WGS_1984_5 8037 Egypt
ED_1950_TO_WGS_1984_6 8038 Ireland, United Kingdom
ED_1950_TO_WGS_1984_7 8039 Finland, Norway
ED_1950_TO_WGS_1984_8 8040 Greece
ED_1950_TO_WGS_1984_9 8041 Iran
ED_1950_TO_WGS_1984_10 8042 Italy (Sardinia)
ED_1950_TO_WGS_1984_11 8043 Italy (Sicily)
ED_1950_TO_WGS_1984_12 8044 Malta
ED_1950_TO_WGS_1984_13 8045 Portugal, Spain
ED_1950_TO_WGS_1984_14 8148 Tunisia
EGYPT_1907_TO_WGS_1984 8048 Egypt

GGRS_1987_TO_WGS_1984 8181 Greek GRS
HUNGARIAN_1972_TO_ETRS_1989_1 8182 Hungarian to ETRS 1989
NZGD_1949_TO_WGS_1984 8051 New Zealand
HU_TZU_SHAN_TO_WGS_1984 8052 Taiwan
INDIAN_1954_TO_WGS_1984 8053 Thailand, Vietnam
INDIAN_1975_TO_WGS_1984 8054 Thailand
KALIANPUR_TO_WGS_1984_1 8055 Bangladesh
KALIANPUR_TO_WGS_1984_2 8056 Indian, Nepal
KALIANPUR_TO_WGS_1984_3 8150 Pakistan
KANDAWALA_TO_WGS_1984 8057 Sri Lanka
KERTAU_TO_WGS_1984 8058 West Malaysia, Singapore

LEIGON_TO_WGS_1984 8059 Ghana
LIBERIA_1964_TO_WGS_1984 8060 Liberia
LUZON_1911_TO_WGS_1984_1 8061 Philippines (excluding Mindanao)
LUZON_1911_TO_WGS_1984_2 8062 Philippines (Mindanao)
MPORALOKO_TO_WGS_1984 8063 Gabon
MAHE_1971_TO_WGS_1984 8064 Mahe Island
MASSAWA_TO_WGS_1984 8065 Ethiopia (Eritrea)
MERCHICH_TO_WGS_1984 8066 Morocco
MINNA_TO_WGS_1984_1 8067 Cameroon
MINNA_TO_WGS_1984_2 8068 Nigeria
MONTE_MARIO_TO_WGS_1984 8069 Italy (Sardinia)
 

NAD_1927_TO_WGS_1984_1 8070 Mean for Antigua, Barbados, Barbuda,

 Caicos Islands, Cuba, Dominican
 Republic, Grand Cayman, Jamaica, and
 Turks Islands

NAD_1927_TO_WGS_1984_2 8071 Mean for Belize, Costa Rica, El

 Salvador, Guatemala, Honduras, and
 Nicaragua

NAD_1927_TO_WGS_1984_3 8072 Mean for Canada
NAD_1927_TO_WGS_1984_4 8073 Mean for United States (CONUS)
NAD_1927_TO_WGS_1984_5 8074 Mean for United States (CONUS East of

 Mississippi River including MN, MO, LA)

NAD_1927_TO_WGS_1984_6 8075 Mean for United States (CONUS West

 of Mississippi River)

NAD_1927_TO_WGS_1984_7 8076 United States (Alaska)
NAD_1927_TO_WGS_1984_8 8077 Bahamas (except San Salvador Island)
NAD_1927_TO_WGS_1984_9 8078 Bahamas (San Salvador Island)
NAD_1927_TO_WGS_1984_10 8079 Canada (Alberta, British Columbia)
NAD_1927_TO_WGS_1984_11 8080 Canada (Manitoba, Ontario)
NAD_1927_TO_WGS_1984_12 8081 Canada (New Brunswick,

 Newfoundland, Nova Scotia, and
 Quebec)

NAD_1927_TO_WGS_1984_13 8082 Canada (Northwest Territories,

 Saskatchewan)

NAD_1927_TO_WGS_1984_14 8083 Canada (Yukon)
NAD_1927_TO_WGS_1984_15 8084 Panama (Canal Zone)
NAD_1927_TO_WGS_1984_16 8085 Cuba
NAD_1927_TO_WGS_1984_17 8086 Greenland (Hayes Peninsula)
NAD_1927_TO_WGS_1984_18 8087 Mexico
NAD_1927_TO_WGS_1984_21 8152 United States (Alaska - Aleutians

 East of 180E)

NAD_1927_TO_WGS_1984_22 8153 United States (Alaska - Aleutians

 West of 180E)

NAD_1983_TO_WGS_1984_1 8088 Canada, Central America, Mexico, and

 United States  (Alaska, CONUS)

NAD_1983_TO_WGS_1984_2 8154 United States (Alaska - Aleutians)
NAD_1983_TO_WGS_1984_3 8155 United States (Hawaii)
NAHRWAN_1967_TO_WGS_1984_1 8089 Oman (Nasirah Island)
NAHRWAN_1967_TO_WGS_1984_2 8090 Saudi Arabia
NAHRWAN_1967_TO_WGS_1984_3 8091 United Arab Emirates
NAPARIMA_1972_TO_WGS_1984 8092 Trinidad & Tobago
NTF_TO_WGS_1984 8093 France
OSGB_1936_TO_WGS_1984_1 8095 Mean for UK (England, Scotland, Wales,

 and Isle of Man)

OSGB_1936_TO_WGS_1984_2 8096 UK (England)
OSGB_1936_TO_WGS_1984_3 8097 UK (England, Wales, and Isle of Man)
OSGB_1936_TO_WGS_1984_4 8098 UK (Scotland, including Shetland

 Islands)

OSGB_1936_TO_WGS_1984_5 8099 UK (Wales)
POINTE_NOIRE_TO_WGS_1984 8100 Congo
PSAD_1956_TO_WGS_1984_1 8101 Mean for Bolivia, Chile, Colombia,

 Ecuador, Guyana, Peru, and Venezuela

PSAD_1956_TO_WGS_1984_2 8102 Bolivia
PSAD_1956_TO_WGS_1984_3 8103 Chile (Northern, near 19 deg S
PSAD_1956_TO_WGS_1984_4 8104 Chile (Southern, near 43 deg S
PSAD_1956_TO_WGS_1984_5 8105 Colombia
PSAD_1956_TO_WGS_1984_6 8106 Ecuador
PSAD_1956_TO_WGS_1984_7 8107 Guyana
PSAD_1956_TO_WGS_1984_8 8108 Peru
PSAD_1956_TO_WGS_1984_9 8109 Venezuela
QATAR_TO_WGS_1984 8110 Qatar
QORNOQ_TO_WGS_1984 8111 Greenland (South)
SAD_1969_TO_WGS_1984_1 8112 Mean for Argentina, Bolivia, Brazil, Chile,

 Colombia, Ecuador, Guyana, Paraguay,
 Peru, Trinidad & Tobago, and Venezuela

SAD_1969_TO_WGS_1984_2 8113 Argentina
SAD_1969_TO_WGS_1984_3 8114 Bolivia
SAD_1969_TO_WGS_1984_4 8115 Brazil
SAD_1969_TO_WGS_1984_5 8116 Chile
SAD_1969_TO_WGS_1984_6 8117 Colombia
SAD_1969_TO_WGS_1984_7 8118 Ecuador
SAD_1969_TO_WGS_1984_8 8119 Ecuador (Baltra, Galapagos)
SAD_1969_TO_WGS_1984_9 8120 Guyana
SAD_1969_TO_WGS_1984_10 8121 Paraguay
SAD_1969_TO_WGS_1984_11 8122 Peru
SAD_1969_TO_WGS_1984_12 8123 Trinidad & Tobago
SAD_1969_TO_WGS_1984_13 8124 Venezuela

SAPPER_HILL_1943_TO_WGS_1984 8125 Falkland Islands (East Falkland Island)
SCHWARZECK_TO_WGS_1984 8126 Namibia
SCHWARZECK_TO_WGS_1984_2 8180 Namibia
TANANARIVE_1925_TO_WGS_1984 8127 Madagascar
TIMBALAI_1948_TO_WGS_1984 8128 Brunei, Malaysia (Sabah, Sarawak)
TM65_TO_WGS_1984 8129 Ireland
TOKYO_TO_WGS_1984_1 8130 Mean for Japan, Korea, and Okinawa
TOKYO_TO_WGS_1984_2 8131 Japan
TOKYO_TO_WGS_1984_3 8132 Korea
TOKYO_TO_WGS_1984_4 8133 Okinawa
YACARE_TO_WGS_1984 8134 Uruguay

ZANDERIJ_TO_WGS_1984 8135 Suriname
HERAT_NORTH_TO_WGS_1984 8149 Afghanistan
INDONESIAN_1974_TO_WGS_1984 8151 Indonesia
NORD_SAHARA_1959_TO_WGS_1984 8156 Algeria
PULKOVO_1942_TO_WGS_1984 8157 Russia
VOIROL_UNIFIE_1960_TO_WGS_1984 8158 Algeria
FAHUD_TO_WGS_1984 8159 Oman
 

NAD_1983_To_NAD_1927_NADCON 108001 NAD27 to NAD83 - CONUS
NAD_1983_To_NAD_1927_Alaska 108002 NAD27 to NAD83 - Alaska
NAD_1983_To_NAD_1927_PR_VI 108003 NAD27 to NAD83 - Puerto Rico, Virgin Islands

NAD_1983_To_Old_Hawaiian 108004 Hawaii
NAD_1983_To_St_George 108005 St. George Island
NAD_1983_To_St_Lawrence 108006 St. Lawrence Island
NAD_1983_To_St_Paul 108007 St. Paul Island

NAD_1983_To_HARN_Alabama 108101 Alabama HARN
NAD_1983_To_HARN_Arizona 108102 Arizona HARN
NAD_1983_To_HARN_CA_N 108103 California North HARN - above 36N
NAD_1983_To_HARN_CA_S 108104 California South HARN - below 37N
NAD_1983_To_HARN_Colorado 108105 Colorado HARN
NAD_1983_To_HARN_Georgia 108106 Georgia HARN

NAD_1983_To_HARN_Florida 108107 Florida HARN
NAD_1983_To_HARN_Kansas 108108 Kansas HARN
NAD_1983_To_HARN_Kentucky 108109 Kentucky HARN
NAD_1983_To_HARN_Louisiana 108110 Louisiana HARN
NAD_1983_To_HARN_MD_DE 108111 Maryland & Delaware HARN
NAD_1983_To_HARN_Maine 108112 Maine HARN
NAD_1983_To_HARN_Michigan 108113 Michigan HARN
NAD_1983_To_HARN_Mississippi 108114 Mississippi HARN
NAD_1983_To_HARN_East_MT_ID 108115 Idaho & Montana HARN - E of 113W
NAD_1983_To_HARN_West_MT_ID 108116 Idaho & Montana HARN - W of 113W

NAD_1983_To_HARN_Nebraska 108117 Nebraska HARN
NAD_1983_To_HARN_Nevada 108118 Nevada HARN
NAD_1983_To_HARN_New_England 108119 New England -CT,MA,NH,RI,VT HARN
NAD_1983_To_HARN_New_Mexico 108120 New Mexico HARN
NAD_1983_To_HARN_Ohio 108121 Ohio HARN
NAD_1983_To_HARN_Oklahoma 108122 Oklahoma HARN
NAD_1983_To_HARN_PR_VI 108123 Puerto Rico & Virgin Islands HARN
NAD_1983_To_HARN_Tennessee 108124 Tennessee HARN
NAD_1983_To_HARN_East_Texas 108125 Texas HARN - E of 100W

NAD_1983_To_HARN_West_Texas 108126 Texas HARN - W of 100W
NAD_1983_To_HARN_Virginia 108127 Virginia HARN
NAD_1983_To_HARN_Utah 108128 Utah HARN
NAD_1983_To_HARN_WA_OR 108129 Washington & Oregon HARN
NAD_1983_To_HARN_West_Virginia 108130 West Virginia HARN
NAD_1983_To_HARN_Wisconsin 108131 Wisconsin HARN

NAD_1983_To_HARN_Wyoming 108132 Wyoming HARN
 
 
 
 

CONUS = CONtinental United States
HARN = High Accuracy Reference Network, or High Accuracy Regional Network



Examples       ArcView Projection Utility
 
 

Here are some example ways to use the ArcView Projection Utility. They can help you understand the different ways you can project and transform shapefiles.
Only the parameters you need to enter on Steps 2 and 3 are shown here, since they are unique to these examples. It is assumed that you know what to do on Steps 1 and 4, and on the Summary panel. If you don't know what to do on these panels, refer to the Quick Start Tutorial.

US State Plane  to UTM (NADCON)
Transforming Hawaii data
Using WGS84 as a pass-through transformation for Ireland
Custom coordinate system example using Albers as output
Custom coordinate system example for Atlas users using Robinson

Australia data example
Antarctica data example
North Pole example
World example
 
 

Example Scenario: US State Plane to UTM

You maintain data in UTM zone 11N, NAD83. You have just been sent a shapefile in State Plane Coordinate System, NAD27, California Zone 5. You need to change the coordinate system of the new shapefile to match your data. Because the data must move between NAD27 and NAD83, a NADCON conversion is required.

1 Set these parameters on Step 2.
  Coordinate System Type: Projected
  Name: NAD_1927_California_V [26745]
  Units: Foot_US [9003]
2 Check Show Advanced Options, if it is not already checked.
3 Click on the Datum tab. From the Geographic Transformation list, choose NAD_1927_To_NAD_1983_NADCON. Press Next.
4 Answer Yes at the prompt to save the coordinate system information with the shapefile, if you want.

5 Set these parameters on Step 3.
  Coordinate System Type: Projected
  Name: NAD_1983_UTM_Zone_11N [26911]
  Units: Meter [9001]
 

Example Scenario: Transforming Hawaii data

Some Hawaii data requires a geographic transformation to the Old Hawaiian datum. This example shows going from State Plane NAD83 to UTM Zone 4 in NAD27.

1 Set these parameters on Step 2.
  Coordinate System Type: Projected
  Name: NAD_1983_Hawaii_4 [26964]
  Units: Meter [9001]
2 Check Show Advanced Options, if it is not already checked.
3 Click on the Datum tab. From the Geographic Transformation list, choose NAD_1983_To_Old_Hawaiian. Press Next.
4 Answer Yes at the prompt to save the coordinate system information with the shapefile, if you want.
5 Set these parameters on Step 3.
  Coordinate System Type: Projected
  Name: NAD_1927_UTM_Zone_4N [26704]
  Units: Meter [9001]
 

Example Scenario: Using WGS84 as a pass-through transformation, going from Ireland TM65 to European 1950

There are several coordinate systems which do not offer a way to move between them and some other coordinate system. In cases like these, you can use WGS84 as a pass-through transformation. All coordinate systems in the ArcView Projection Utility can go to or from this coordinate system.

1 Set these parameters on Step 2.
  Coordinate System Type: Geographic
  Name: GCS_TM65 [4299]
  Units: Degree [9102]
2 Check Show Advanced Options, if it is not already checked.
3 Click on the Datum tab. From the Geographic Transformation list, choose TM65_To_WGS_1984. Press Next.
4 Answer Yes at the prompt to save the coordinate system information with the shapefile, if you want.
5 Set these parameters on the Step 3 panel, then press Next.
  Coordinate System Type: Projected
  Name: ED_1950_UTM_Zone_28N [23028]
  Units: Meter [9001]

6 Click on the Datum tab. From the Geographic Transformation list, choose WGS_1984_6_To_ED_1950. Note the Area of Use for this transformation is Ireland and United Kingdom, and the POSC code is 8038.
 
 

Example Scenario: Custom coordinate system example using Albers as output

Albers is not a predefined coordinate system in this version of the ArcView Projection Utility. Here's a way to project your data to Albers. This example uses the shapefile named states.shp in the usa folder on the ESRI Maps and Data CD that comes with ArcView 3.2. This shapefile is in Geographic NAD83.

1 You do not need to set anything on the Step 2 panel, since the information stored with the file is populated in the wizard. Press Next.
2 Set these parameters on Step 3.
  Coordinate System Type: Projected
  Name: Custom
  Units: Meter [9001]
3 Click on the Parameters tab and enter these values.
  GeoCSYSName: GCS_North_American_1983 [4269]
  Base Projection: Albers [43007]
  Central Meridian:  -105
  Central Parallel:  0
  Standard Parallel 1: 60
  Standard Parallel 2: 45
 
 

Example Scenario: Custom coordinate system example for Atlas users using Robinson (2 ways)

The data for Atlas at one time was all in NAD27. Since Robinson in NAD27 is not a predefined coordinate system, you can modify the existing Robinson coordinate system instead.

One way:

1 Set these parameters on Step 2.
  Coordinate System Type: Projected
  Name: World_Robinson [54030]
  Units: Meter [9001]
2 Click on the Parameters tab. Enter these values.
  GeoCSYSName: GCS_North_American_1927 [4267]
  Central Meridian:  -100
3 On the Datum tab set the transformation as NAD_1927_To_WGS_1984_4. Press Next.
4 Set these parameters on Step 3.
  Coordinate System Type: Projected
  Name: World_Robinson [54030]
  Units: Meter [9001]

5 Click on the Parameters tab and enter these values.
  GeoCSYSName: GCS_WGS_1984 [4326]
  Central Meridian:  -100

Another way: This example is different than the one above in that it starts with a Custom setting rather than building off the existing Robinson coordinate system. We recommend that when you can't find a coordinate system that matches exactly what you want, it's best to build from a coordinate system that is already defined, and modify it as necessary.

1 Set these parameters on Step 2.
  Coordinate System Type: Projected
  Name: Custom
  Units: Meter [9001]
2 On the Parameters tab enter these parameters.
  GeoCSYSName: GCS_North_American_1927 [4267]
  Base Projection: Robinson [43030]
  Central Meridian:  -100
3 On the Datum tab set the transformation as NAD_1927_To_WGS_1984_4. Press Next.
4 Set these parameters on Step 3.
  Coordinate System Type: Projected
  Name: Custom
  Units: Meter [9001]

5 On the Parameters tab enter these parameters.
  GeoCSYSName: GCS_WGS_1984 [4326]
  Base Projection: Robinson [43030]
  Central Meridian:  -100
 
 

Example Scenario: Australia data example (WGS84 as a pass-through transformation)

There are no predefined ways to move between these coordinate systems, so you must do the transformation in two parts: first go from AGD 1966 to WGS84, then from WGS84 to GDA 1994.

1 Set these parameters on Step 2.
  Coordinate System Type: Projected
  Name: AGD_1966_AMG_Zone_50 [20250]
  Units: Meter [9001]
2 Check Show Advanced Options, if it is not already checked.
3 Click on the Datum tab. From the Geographic Transformation list, choose AGD_1966_TO_WGS_1984. Press Next.
4 Answer Yes at the prompt to save the coordinate system information with the shapefile, if you want.
5 Set these parameters on the Step 3 panel, then press Next.
  Coordinate System Type: Projected
  Name: GDA_1994_MGA_Zone_50 [28350]
  Units: Meter [9001]

6 Click on the Datum tab. From the Geographic Transformation list, choose WGS_1984_To_GDA_1994. Note the Area of Use for this transformation is Australia, and the POSC code is 8050.
 

Example Scenario: Antarctica data example (Stereographic example)

Here's an example for the southern hemisphere.

1 (Depending on what data set you use as an input, you may need to set a transformation on the Datum tab of Step 2.)
2 Set these parameters on Step 3.
  Coordinate System Type: Projected
  Name: World_Stereographic [54026]
  Units: Meter [9001]
3 Click on the Parameters tab and enter these values.
  GeoCSYSName: GCS_Sphere [4035]
  Central Meridian: -72.533333
  Central Parallel: -90
 
 

Example Scenario: North Pole example (Azimuthal Equidistant example)

Here's an example for the northern hemisphere.

1 (Depending on what data set you use as an input, you may need to set a transformation on the Datum tab of Step 2.)
2 Set these parameters on Step 3.
  Coordinate System Type: Projected
  Name: World_Azimuthal_Equidistant [54032]
  Units: Meter [9001]
3 Click on the Parameters tab and enter these values.
  GeoCSYSName: GCS_Sphere [4035]
  Central Meridian: -72.533333
  Central Parallel: 90
 
 

Example Scenario: World example

This example uses the shapefile named cntry98.shp in the world folder on the ESRI Maps and Data CD that comes with ArcView 3.2. This shapefile is in Geographic WGS84.

1 You do not need to set anything on the Step 2 panel, since the information stored with the file is populated in the wizard. Press Next.
2 Set these parameters on Step 3. You do not need to set any other parameters.
  Coordinate System Type: Projected
  Name: World_Mollweide [54009]
  Units: Meter [9001]