topic Re: Problem: empty output raster when using Polygon to raster in Data Management Questions

Problem: empty output raster when using Polygon to raster

MattiasRenström — Sat, 08 Sep 2012 09:46:11 GMT

This is the first time I use this forum, but hopefully I have found the correct subforum for this problem!

I have two polygon layers who I try to turn into raster layers. I use the polygon to raster-tool (Conversation tools -> To raster -> Polygon to raster).

When choosing input features, I choose a polygon layer.
On Value field I choose the field I want to use (vegetation type, can be 0, 1 or 2).
On output raster features, I choose a short name just to be safe.
On cell assignment type, I let it stay on CELL_CENTER.
On Priority field, I choose NONE.
On cell size, i choose 1.

When running this function, the output raster is empty. If I choose "zoom to layer" on the output raster, it moves away from the place where the polygons are, and just shows an empty place. Why does this happen?

Re: Problem: empty output raster when using Polygon to raster

JeffreySwain — Mon, 10 Sep 2012 10:23:17 GMT

If when you try to examine the spatial extent of the output raster and it is vastly different than the original, then perhaps the raster data you have has some other issues involved. Can you try exporting the particular landcover class to a new raster prior to converting to see the spatial extent and projection is correct??

Re: Problem: empty output raster when using Polygon to raster

MattiasRenström — Tue, 11 Sep 2012 14:15:27 GMT

Thank you for the reply.
I got help solving this problem yesterday. It turned out I had used the wrong method converting coordinate system. So the files claimed to use the Swedish Sweref 99, but was in reallity sticking to WGS 84...
Therefor, when I thought I told the Polygon to raster tool I wanted the resolution 1 meter, in reallity I told it to use the resolution 1 degree. I can see problem coming with that resolution! 😄

I suppose I should not click to mark this post as the answer, should I?

Re: Problem: empty output raster when using Polygon to raster

JeffreySwain — Thu, 13 Sep 2012 11:34:12 GMT

If you feel it has been answered, then by all means.