topic Re: How do i get two raster cells to align? in ArcGIS Desktop Deutschland Questions

How do i get two raster cells to align?

Kofi_Lartey — Thu, 02 Mar 2017 01:53:07 GMT

I am converting points to raster and have to match the converted points to a raster image. In converting the points to raster i set the environment to snap to the existing raster and used same cell size and coordinates. However the output is showing raster cells which are slightly displaced, about 3mm displacement. How do i reset the snap so the two cells match exactly? I have tried working both in a gdb environment and outside it but just a slight improvement with the gdb environment. The displacement this time is in one direction, to the North. i am using arcmap 10.1

Re: How do i get two raster cells to align?

DanPatterson_Retired — Thu, 02 Mar 2017 02:57:01 GMT

it isn't just the extent, it is also the snap raster... some reading

http://desktop.arcgis.com/en/arcmap/latest/tools/environments/snap-raster.htm

http://desktop.arcgis.com/en/arcmap/latest/tools/environments/how-snap-raster-environment-works.htm

http://desktop.arcgis.com/en/arcmap/latest/manage-data/raster-and-images/environment-settings-for-raster-data.htm

if memory serves, it still applies to 10.1, but you can check the legacy help files on the main help link

Re: How do i get two raster cells to align?

NeilAyres — Thu, 02 Mar 2017 07:26:15 GMT

Yes, when I am creating raster from whatever source, I always explicitly set the extents to be exactly the same, as well as setting the snap raster.

To get the extent, just view the input data in ArcMap, then draw a graphic box around it using the draw tools. Then edit the starting points and width/height to exact meters (or whatever unit you data is in). Obviously this also has to take in what cellsize you want.