Accepted Solutions
Yes you can do this, but it is not a very good thing to do, to overlay rasters that have different resolutions and don't seem to align. But, if this is what you have and you still want to proceed, you can do this with the Raster Calculator (I assume you have Spatial Analyst):
With this formula, you will create a new raster that will have the values of the second raster where the first raster is Null (has NoData. If the first raster has values, they will be written to the output.
Before you press OK, you should enter the Environments and specify how to handle the difference of resolution. Set Processing Extent to the raster you want to use (or use Union for the combination of both extents or Intersect for the area they have in common) and select the Snap Raster (also in Processing Extent) . Set the Cell Size in Raster Analysis.
Although you define how the output should be created you have little influence over how partly covered cells will be handled.
You could also convert both rasters to polygons, perform a union and using the attribute table of the resulting featureclass, guide the way you want your outcome to be (write this to a new field). The result can be converted back to raster (using the field you created in the previous step).
Yes you can do this, but it is not a very good thing to do, to overlay rasters that have different resolutions and don't seem to align. But, if this is what you have and you still want to proceed, you can do this with the Raster Calculator (I assume you have Spatial Analyst):
With this formula, you will create a new raster that will have the values of the second raster where the first raster is Null (has NoData. If the first raster has values, they will be written to the output.
Before you press OK, you should enter the Environments and specify how to handle the difference of resolution. Set Processing Extent to the raster you want to use (or use Union for the combination of both extents or Intersect for the area they have in common) and select the Snap Raster (also in Processing Extent) . Set the Cell Size in Raster Analysis.
Although you define how the output should be created you have little influence over how partly covered cells will be handled.
You could also convert both rasters to polygons, perform a union and using the attribute table of the resulting featureclass, guide the way you want your outcome to be (write this to a new field). The result can be converted back to raster (using the field you created in the previous step).
Ah yes, I forgot it that time. Now it workes just like I wanted, even if I do not totally understand at wich level of share partly covered cells are defined the one or the other value.
Thanks a lot for the patient explanation! 
.png "KishorGhatage"){kind=avatar}
