topic Re: IDW Interpolation - 3D Bathymetry in ArcGIS Spatial Analyst Questions

IDW Interpolation - 3D Bathymetry

PaulEvans — Wed, 07 Dec 2011 17:36:39 GMT

Dear all,

I have created a raster from bathymetric data points using the IDW interpolation method using a 2m cell size. When I add the raster to ArcScene and adjust the parameters, such as increase the raster resolution and increase the quality enhancement to maximum in the rendering tab I seem to get what look like pot holes in the surface (as shown on the attached?

Does anyone know why this might be?

Any help would be greatly appreciated as I would like to use this data in an important conference at the end of the week.

Thanks,

Paul

Re: IDW Interpolation - 3D Bathymetry

TimothyHales — Thu, 08 Dec 2011 12:52:10 GMT

What is the average point spacing of your points? Do your points coincide with each of those depressions? Have you tried creating a TIN with the data to see if you get different results?

Re: IDW Interpolation - 3D Bathymetry

PaulEvans — Thu, 08 Dec 2011 17:25:09 GMT

Hi there,

Thanks for your prompt response. The point spacing varies as it is based on both charted and surveyed data. I have attached a screenshot of the data with the raw data points and it does indeed look like the depressions coincide with these points.

Any ideas why this might be?

I will try and create a TIN now and see how it looks.

Kind regards,

Paul