topic Re: Hillshade Creation Problem in ArcGIS Spatial Analyst Questions

Hillshade Creation Problem

RyanSuemnicht — Wed, 19 Sep 2012 18:37:22 GMT

Hello, I am trying to use the Hillshade tool in the Spatial Analyst toolset from ArcToolbox. I am trying to make a hillshade from USGS 10 meter DEMs that are mosaicked together. When I created a hillshade from this data, the hillshade was created properly up to the first horizontal line in the footprint (attachment) Aside from that area, the rest of the hillshade is grey and shows no texture. I used all of the default settings when using the hillshade tool, I just inputted the necessary raster and output folder.

Thanks, Ryan

Re: Hillshade Creation Problem

EricRice — Wed, 19 Sep 2012 19:30:25 GMT

Ryan,

Have you thought about using a hillshade function on your mosaic dataset? That way you don't have to store the hillshade. It will be produced on the fly from the source dem data.

Eric

Re: Hillshade Creation Problem

RyanSuemnicht — Wed, 19 Sep 2012 19:47:45 GMT

Yes I have. Having the hillshade under a slightly transparent DEM will give the terrain the right look. Would a missing portion in the DEM cause a problem like this? I just noticed the boundary I am using has a small corner missing right along the edge of the DEM.

Thanks, Ryan

Re: Hillshade Creation Problem

EricRice — Wed, 19 Sep 2012 20:24:19 GMT

Ryan,

You should be able to input a mosaic dataset into the Hillshade GP tool assuming your not exceeding the maximum request size limit specified in the mosaic dataset properties. The tool would fail if it requested more than allowed. It wouldn't process anything, so there is something else going on.

If the goal is to make a tinted hillshade using some transparency on the DEM (with color) overlaid on the hillshade, you can still do this with just functions. Check out the blog, An alternative to overlaying layer tints on hillshades.

Eric

Re: Hillshade Creation Problem

RyanSuemnicht — Thu, 20 Sep 2012 01:54:29 GMT

Eric,

I looked into the alternative method you suggested and it will not work because I do not have a hillshade of the dataset. I need to know what is stopping the hillshade from creating properly at the first line of the footprint. Then I will be able to create the hillshade and try this method.

Thanks, Ryan

Re: Hillshade Creation Problem

EricRice — Fri, 21 Sep 2012 16:10:14 GMT

Ryan,

What happens when you apply a hillshade function to the mosaic dataset? You know you can make a reference mosaic dataset from the original right? One would have the hillshade function, and one would be the dem, both from the same source data. If you have Support I would suggest creating an incident so an analyst can connect with you.

Also, in the blog I sent, there is a link to another blog that only uses functions, rather than the image analysis window to create the hillshade and layer tint. The other blog indicates you need a colormap file though, which you would have to create.

Lastly, have a look at the shaded relief function. It's like hillshade but it colored.

Best,
Eric

Re: Hillshade Creation Problem

RyanSuemnicht — Mon, 24 Sep 2012 12:48:47 GMT

Hi Eric,
Thanks for your suggestions on an alternate methods to creating a hillshade. I've tried these different methods and had bad luck for one reason or another. What I want to do is create a hillshade using the Arctoolbox tool under spatial analyst-surface-hillshade. I've used this method in previous versions of Arc (I now have Arc10) and I'm familiar with it. This is the method I would like to use, but for some reason it's only creating the hillshade partway and stopping. Any ideas why this is?

Thanks,
Ryan