topic Re: Problem when Projecting a raster file. in Data Management Questions

Problem when Projecting a raster file.

SouryanaNasseraldin — Mon, 20 Jan 2014 09:05:34 GMT

Hi!
I have a problem when projecting a raster file.
The tool I am using is Project Raster. I have a grid file of Landuse in Africa:

COORDINATE REFERENCE
TYPE Projected
PROJECTION lambert
GEOGRAPHIC COORDINATE REFERENCE GCS_Lambert
COORDINATE REFERENCE DETAILS
PROJECTED COORDINATE SYSTEM
X ORIGIN -200
Y ORIGIN -5385200
XY SCALE 22517998136852.477
Z ORIGIN -100000
Z SCALE 10000
M ORIGIN -100000
M SCALE 10000

I want to project it to:
Africa_Albers_Equal_Area_Conic
Projection: Albers
False_Easting: 0.000000
False_Northing: 0.000000
Central_Meridian: 25.000000
Standard_Parallel_1: 20.000000
Standard_Parallel_2: -23.000000
Latitude_Of_Origin: 0.000000
Linear Unit: Meter (1.000000)

Geographic Coordinate System: GCS_WGS_1984
Angular Unit: Degree (0.017453292519943299)
Prime Meridian: Greenwich (0.000000000000000000)
Datum: D_WGS_1984

When I want to project it the whole program shuts down. I Dont know What I am doing wrong. I have tried everything. I also set the environmental settings but that didnt help either. I also should mention that I have service pack 5 installed but still the projection didnt work out.
I would be very please if anyone could help me solve this issue.
Regards

Re: Problem when Projecting a raster file.

NeilAyres — Tue, 21 Jan 2014 05:49:21 GMT

What format is your input, because this doesn't look like anything ArcGIS would put out :
"COORDINATE REFERENCE
TYPE Projected
PROJECTION lambert
GEOGRAPHIC COORDINATE REFERENCE GCS_Lambert
COORDINATE REFERENCE DETAILS
PROJECTED COORDINATE SYSTEM
X ORIGIN -200
Y ORIGIN -5385200
XY SCALE 22517998136852.477
Z ORIGIN -100000
Z SCALE 10000
M ORIGIN -100000
M SCALE 10000"
Possibly CAD or something...
Neil

Re: Problem when Projecting a raster file.

SouryanaNasseraldin — Tue, 21 Jan 2014 08:11:03 GMT

The file is in GRID fromat. The thing is that I am doing an assignment for a course. And when I define the file, it was correct because I gave my teachers said the parameters where OK efter I defined it. But now I have to project it and it doesnt work. Also the datum is in D_Sphere_ARC_INFO and it has to be in WGS84 when I project it. I dont know if thats where the problem is.

This is the spatial reference. Due to the parameters that I got for Land Cover it was not a pre defined option for me in ArcGIS so I had to create a new projected coordinate system called Lambert.

Spatial reference Lambert
Linear Unit              Meter (1.000000)
Angular Unit            Degree (0.017453292519943299)
False easting           0
False Northing          0
Central Meridian       200000
Latitude of origin      50000
Datum               D_Sphere_ARC_INFO

Regards

Re: Problem when Projecting a raster file.

NeilAyres — Tue, 21 Jan 2014 17:00:27 GMT

Sorry, old workstation grid format (watch the oldies throw rocks at me....), should have picked up on that.

But this spatial reference definition :

Spatial reference Lambert
Linear Unit Meter (1.000000)
Angular Unit Degree (0.017453292519943299)
False easting 0
False Northing 0
Central Meridian 200000
Latitude of origin 50000
Datum D_Sphere_ARC_INFO

It seems, at least, that you are confusing the X/Y shifts (False Easting / Northing) with the central meridian, Lat of Origin.
Those values for the Central Meridian should be a value of the longitude of the central meridian of the projection.
Ditto the Lat of origin (usually 0 , the equator).
But again the original description looks really odd, where are the standard parallels info.
So until you get the source spatial reference definitions correct, you can't project this correctly.

Here is what I get looking at a grid datasets in Catalog.

Re: Problem when Projecting a raster file.

MelitaKennedy — Sat, 11 Dec 2021 18:17:18 GMT

Hello,

I think the

Central Meridian 200000
Latitude of origin 50000

are really:

Central Meridian 20 00 00
Latitude of origin 5 00 00

in degrees minutes seconds. The values make sense for Africa, anyway. The standard parallel values are missing if the projection is Lambert conformal conic. Can you find the prj.adf file for this grid file and post its contents? It will be in the grid's folder. You won't be able to access it through ArcCatalog.

It might really be Lambert Azimuthal equal area which won't have standard parallel values.

Beyond that, there are no defined transformations between a sphere-based geographic coordinate system and a geodetic datum (geodetically-defined geographic coordinate reference system). The project raster tool may be having a problem because there is no available transformation.

Instead, I would add the raster to ArcMap with some reference data you can overlay. Set the data frame to your target coordinate reference system. Does this layer line up? If so, right-click the layer and export it, using the data frame's coordinate system.

If there's a consistent north-south offset instead, try defining a custom transformation first.

Open the data frame's properties and select the coordinate system tab.

Click the Transformations button.

On that dialog, click the New button.

Select geocentric translation for the method and leave the parameter values set to zeroes.

OK all dialogs and see if the data aligns better. If so, now export it using the data frame's coordinate system.

Melita

Re: Problem when Projecting a raster file.

SouryanaNasseraldin — Wed, 22 Jan 2014 11:23:30 GMT

Hi!

Thanks for the help. I solved the problem. I had written the degrees incorrect and I should have written 20 00 00 and not 200000.. So thanks for the help really. I have another problem now. the projected layer is not "straight" anymore. I will attach a pic, representing the resulting layer, with this e mail. I dont know what the problem is... Do you have any suggestions?

thanks in advance

Re: Problem when Projecting a raster file.

MelitaKennedy — Wed, 22 Jan 2014 15:51:29 GMT

Hi,

That implies that there's something wrong with the original coordinate system definition. What happens if you display the original data with some other, known good data like country boundaries? I think it won't overlay correctly which would confirm that the original's coordinate system isn't correct.

Can you post the prj.adf contents?

Melita

Re: Problem when Projecting a raster file.

SouryanaNasseraldin — Thu, 23 Jan 2014 07:53:58 GMT

Hi!
Ok.. I will send you a picture of what I type when I want to define the layer.
regards

Re: Problem when Projecting a raster file.

SouryanaNasseraldin — Thu, 23 Jan 2014 08:42:54 GMT

And this is the prj information that you want?
Regards

Re: Problem when Projecting a raster file.

MelitaKennedy — Sat, 11 Dec 2021 18:17:21 GMT

Maybe!

If the last image you posted is using Albers equal area.

If the original data was a raster in GRID format, you should be able to browse to its folder using Windows. In the grid file's folder, there should be a prj.adf file. It's a text file, so you can open it with Notepad. I expect that it looks something like:

PROJECTION LAMBERT_AZIMUTH
UNITS METERS
SPHEROID SPHERE
PARAMETERS
6370997.0
20 0 0.0
5 0 0.0
0.0
0.0

If it doesn't, then maybe that's the problem. What happens if you add the original raster to a new ArcMap session, and set the data frame to be WGS 1984 and change the display units to degrees. As you move the cursor around the data, do the reported latitude and longitude values make sense?

Melita

Re: Problem when Projecting a raster file.

SouryanaNasseraldin — Fri, 24 Jan 2014 11:21:58 GMT

Hi!
The original file was a *bsq. file. So I converted the file to an ESRI GRID file using Raster To Other Format- tool. I chose GRID as Raster format. But there arent any prj.adf file in the original file (after a converted the file to a grid format).. Should there exist a file like that? But after I define the grid layer I get a prj.adf file and it looks like this:

Projection    LAMBERT_AZIMUTHAL
Spheroid      SPHERE
Units         METERS
Zunits        NO
Xshift        0.0
Yshift        0.0
Parameters
6370997.0 /* radius of the sphere of reference
20 0 0.0 /* longitude of center of projection
   5 0 0.0 /* latitude of center of projection
0.0 /* false easting (meters)
0.0 /* false northing (meters)

regards

Re: Problem when Projecting a raster file.

SouryanaNasseraldin — Fri, 24 Jan 2014 11:35:39 GMT

The last image I posted was an Africa Albers Equal Area Conic projection. That was when I projected the layer and not when I defined the layer. Sorry I should have mention it.

I opened the properties of the data frame (where the map looks normal and not like in the pic above) and saw that the datum was in D_Sphere_ARC_INFO. And when I open the map in a new data frame and checked the properties for the new data frame it changed to WGS_84 and thats when the map looks strange. Whats the problem here then? Do you think theres something wrong with the transformation from D_Sphere_ARC_INFO to WGS_84 when I project the file?

regards