Windisp Documentation
Converting a grid from one projection and datum to another.
This example converts a WGS84 UTM zone 10 grid to NAD27 UTM Zone 10.
1)Open Windisp and set the projection information to the projection of the source grid
Edit >  Area Limits, Scale, and projection
Projection tab > scale:100000
frame type: Easting/Northing
projection: Universal Transverse Mercator
Zone number: 10
Hemisphere: Northern
Spheroid: WGS84
Done
2)Load the image file and check it
Edit > images    - select image to display and transform
Display grid details – all OK?
Copy image limits to Plot limits (top of image file specification panel) Done
3)Check the image, then go back to the image menu and transform it
Edit > images >transform grid
Transform using “Convert Geographic Grid”
Current grid coordinates  “grid”
Tick “use same projection as current layout”
Cont’d…
Define Projection and Datum Transform
Check source datum and projection info: ie expect UTM, WGS84, Zone 10N
Enter name for transform in Transform entry “WGS84 to NAD27 NWT Z10”
Enter DX, DY, DZ for WGS84 to NAD27 & Scale: -4.0, -159, -188, 0.9996 Save to store values for future use, note they now appear in the pulldown list.
Test the transform
In ”Source Data coordinates” (top half of panel)
Enter reasonable values for East and North: 500000, 8000000
Try: “East/North ->Lat/lon” , get reasonable answer 123 0 0.000 E, 72 5 57.201N
Try “convert Source data to map”, get reasonable answer below
In Convert Source Data to Map (bottom half of panel)
Try “Lat/lon -> East/North” get reasonable answer, note shift values reported DONE  (tested transformation parameters, now return to Define Source Datum Definitions panel
DONE (now return to Grid Transformations and transform grid)
Set output  cell size: 150, 150
Output file name “DEM-G_NAD27”
File Format: “Geosoft”
Perform Transformation
( this will transform the grid using the following steps:  projected coordinate system  > source geographic > datum shift >target geographic >
projected coordinate system)
Wait for transformation complete button – press “OK”
Cont’d…
For next grid, load image file, display and repeat steps.  Note that the transformation parameters are  already loaded now, so one can proceed through a series of grids sequentially.
To check the transformation, contour a target grid, and then display the image from the corresponding source grid, with the the contours from the target grid laid over.  The displacement should be as expected.
Note that the scale of the target projection needs to be provided, as the algorithm goes from projection, to geographic cords, does the datum change, and then reprojects into the target projection.  For NAD27 UTM the scale is “0.9996”.  This is the same as the scale of the WGS84 UTM projection system. Converting a database from one projection and datum to another.
This example converts a WGS84 UTM zone 10 XYZ to WGS84 UTM Zone 9 XYZ.
1)Open Windisp and select Edit – Posting – Select Posting File – Text file (text file is appropriate for
importing an XYZ)
2)Select X and Y channels and Define Projection and Datum Transform
Projection – UTM
Spheroid – WGS84
Zone – 10
3)Keep all remaining settings as default.  Click OK.
4)Select data variables to be exported.  It is not necessary to reselect the X and Y channels.  Click
on Display Data Range to import the data.
5)Select OK and exit Data Posting Specification.
6)To change projection, Edit – Posting – Edit Posting Specification
7)Click on Define Coordinates.  Be sure to check OFF Use same projection as current layout.
Otherwise the transform will not work.  Click on Define Projection and Datum Transform.
Change UTM zone to 9.
Optional – To test if transform has worked, enter an Easting/Northing into the Source Data
Coordinates.  Click East/North->Lat/Long button to get Lat/Long coordinates.  Click Convert
Source Data to Map button.  The new Lat/Long coordinates will appear.  Click Lat/Long->
East/North button to covert to UTMs.  The Distance and Azimuth should be representative of
the transform.  Click Done and Done, then click OK.
8)In Data Posting Specification, Click Export Data.  Note - you may need to click on Define Data
Variable to change number of decimal places (default is 2).  Choose a new filename for the
exported data and click OK.
9)The exported XYZ should be in the new projection.
A list of common datum conversions to WGS84 follows:
Datum transforms from local datum to WGS84
[Datums]
Adindan=Clarke 1880
Afgooye=Krassovsky 1940,-43,-163,45,Somalia
Ain el Abd 1970=International 1924
American Samoa 1962=Clarke 1866,-115,118,426,American Samoa Islands
Anna 1 Astro 1965=Australian National,-491,-22,435,Cocos Islands
Antigua Island Astro 1943=Clarke 1880,-270,13,62,Antigua (Leeward
Islands)
Arc 1950=Clarke 1880
Arc 1960=Clarke 1880
Ascension Island 1958=International 1924,-205,107,53,Ascension Island
Astro Beacon E 1945=International 1924,145,75,-272,Iwo Jima
Astro DOS 71/4=International 1924,-320,550,-494,St Helena Island
Astro Tern Island (FRIG) 1961=International 1924,114,-116,-333,Tern
Island
Astronomical Station 1952=International 1924,124,-234,-25,Marcus Island Australian Geodetic 1966=Australian National,-133,-48,148,Australia, Tasmania
transform和convert的区别Australian Geodetic 1984=Australian National,-134,-48,149,Australia, Tasmania
Ayabelle Lighthouse=Clarke 1880,-79,-129,145,Djibouti
Bellevue (IGN)=International 1924,-127,-769,472,Efate and Erromango Islands
Bermuda 1957=Clarke 1866,-73,213,296,Bermuda
Bissau=International 1924,-173,253,27,Guinea-Bissau
Bogota Observatory=International 1924,307,304,-318,Colombia
Bukit Rimpah=Bessel 1841,-384,664,-48,Indonesia (Bangka and Belitung Ids) Camp Area Astro=International 1924,-104,-129,239,Antarctica (McMurdo Camp Area)
Campo Inchauspe=International 1924,-148,136,90,Argentina
Canton Astro 1966=International 1924,298,-304,-375,Phoenix Islands
Cape=Clarke 1880,-136,-108,-292,South Africa
Cape Canaveral=Clarke 1866,-2,151,181,Bahamas, Florida
Carthage=Clarke 1880,-263,6,431,Tunisia
Chatham Island Astro 1971=International 1924,175,-38,113,New Zealand (Chatham Island)
Chua Astro=International 1924,-134,229,-29,Paraguay
Corrego Alegre=International 1924,-206,172,-6,Brazil
Dabola=Clarke 1880,-83,37,124,Guinea
Deception Island=Clarke 1880,260,12,-147,Deception Island, Antarctia Djakarta (Batavia)=Bessel 1841,-377,681,-50,Indonesia (Sumatra)
DOS 1968=International 1924,230,-199,-752,New Georgia Islands (Gizo Island)
Easter Island 1967=International 1924,211,147,111,Easter Island
European 1950 (ED 50)=International 1924
European 1979 (ED 79)=International 1924
Fort Thomas 1955=Clarke 1880,-7,215,225,Nevis, St. Kitts (Leeward Islands)
Gan 1970=International 1924,-133,-321,50,Republic of Maldives
Geodetic Datum 1949=International 1924,84,-22,209,New Zealand
Graciosa Base SW 1948=International 1924
Guam 1963",Clarke 1866,-100,-248,259,Guam
Gunung Segara=Bessel 1841,-403,684,41,Indonesia (Kalimantan)
GUX 1 Astro=International 1924,252,-209,-751,Guadalcanal Island
Herat North=International 1924,-333,-222,114,Afghanistan
Hjorsey 1955=International 1924,-73,46,-86,Iceland
Hong Kong 1963=International 1924,-156,-271,-189,Hong Kong
Hu-Tzu-Shan=International 1924,-637,-549,-203,Taiwan
Indian (Bangladesh)=Everest (India 1830),282,726,254,Bangladesh
Indian (India, Nepal)=Everest (India 1956),295,736,257,India, Nepal
Indian (Pakistan)=Everest (Pakistan),283,682,231,Pakistan
Indian 1954=Everest (India 1830),217,823,299,Thailand
Indian 1960=Everest (India 1830)
Indian 1975=Everest (India 1830),209,818,290,Thailand
Indonesian 1974=Indonesian 1974,-24,-15,5,Indonesia
Ireland 1965=Modified Airy,506,-122,611,Ireland
ISTS 061 Astro 1968=International 1924,-794,119,-298,South Georgia Islands
ISTS 073 Astro 1969=International 1924,208,-435,-229,Diego Garcia
Johnston Island 1961=International 1924,189,-79,-202,Johnston Island Kandawala=Everest (India 1830),-97,787,86,Sri Lanka
Kerguelen Island 1949=International 1924,145,-187,103,Kerguelen Island Kertau 1948=Everest (Malay. and Singapore 1948),-11,851,5,West Malaysia and Singapore
Kusaie Astro 1951=International 1924,647,1777,-1124,Caroline Islands L. C. 5 Astro 1961=Clarke 1866,42,124,147,Cayman Brac Island
Leigon=Clarke 1880,-130,29,364,Ghana
Liberia 1964=Clarke 1880,-90,40,88,Liberia
Luzon=Clarke 1866
M'Poraloko=Clarke 1880,-74,-130,42,Gabon
Mahe 1971=Clarke 1880,41,-220,-134,Mahe Island

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