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I'm looking to create a raster such that the edges of the raster are aligned perfectly with the cartesian coordinates of the underlying projection.

I am using a custom Lambert conformal conic projection, so the coordinate 0,0 is in my study area and I would like that to be either the center of each cell or one of the corners and each cell extending outwards would have be a multiple of 200.

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Hi Jim, what software are you using? –  Michael Miles-Stimson Jun 19 at 4:29
    
I am using ArcGIS; I thought of creating a set of coordinates for a point file and then doing a point to raster conversion, but there must be an easier way. Thanks for responding! Much appreciated. –  Jim Richalds Jun 19 at 4:34
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What sort of raster/what values do you want to create? –  Luke Jun 19 at 5:15
    
I want to use it as a snap raster for resampling and reprojecting another raster, so the value doesn't matter I guess. –  Jim Richalds Jun 19 at 5:53
    
@Jim - I've updated my answer to show how to create the raster. –  Luke Jun 19 at 22:31

2 Answers 2

Open the Create Constant Raster tool. Set your Environment output extent and cellsize appropriately and create your raster and you're done.

For example:

  1. Set extent to 0 0 2000 2000 and a cellsize of 200 to create a 10 by 10 raster with the lower left corner at 0,0.
  2. Set extent to -100 -100 1900 1900 and a cellsize of 200 to create a 10 by 10 raster with the centre of the lower left pixel at 0,0.
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I have felt this pain before! What you need to do is get a JPEG, any old image, and create a world file with these parameters:

200
0
0
-200
0
0

Use notepad to create the file and then rename .txt to .jgw, the base file name should be exactly the same as the jpeg, for example if the image is Family.jpg the world is Family.jgw. Now it's falsely georeferenced. In your environment settings set this as Snap Raster so if you do something like polygon to raster its cells will align with that georeference.

Now, set your output extent to start at 0,0 and extend to cover all (and some) of your inputs. Now when geoprocessing rasters the cells will align with and start at 0,0.

Be aware though that some tools will shrink the extent if it is all NoData to the left and will not actually start at 0,0; to get around this you can try put in a fake feature at -1,-1 which will be trimmed off by the extent. Even then you may experience shrinkage if there's all NoData.

Another option is to make the background a value and then set the NoData value via catalog after processing. This all depends on which tool(s) you are attempting to use.

To create a fresh (empty) raster you can use Create Raster Dataset with these settings, though width and height are not implicitly set in the tool it should get enough cells to cover the Extent environment. To create a raster filled with a background value create a polygon feature class, make it the same spatial reference as your data, edit it in ArcMap and draw a box polygon big enough (absolute x,y might help here) and then use Polygon to Raster to convert it into a raster dataset.

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