topic Re: Creating a Hillshade from Mosaic DEM in ArcGIS Spatial Analyst Questions

Creating a Hillshade from Mosaic DEM

MikeMichalek — Fri, 24 Feb 2012 15:17:17 GMT

I am having problems creating a Hillshade from a mosaic DEM I made with 10m USGS seamless data DEM's. I go to the Spatial Analyst tool "Hillshade" and create the new hillshade layer, but the output is a grey screen in which you can view lines where the individual USGS DEM's boundaries were, not a hillshade. I was wondering if anyone knew what I could do to fix this.

(Screen Captures Attached)

Thanks,

Mike

Re: Creating a Hillshade from Mosaic DEM

JoeFlannery — Fri, 24 Feb 2012 15:22:35 GMT

Mike:

Have you run Statistics on your DEM mosaic?
Also, you can "Symbolize" your DEM for hillshade.
>Layer Properties >Symbology tab >check on "Use hillshade effect"

Re: Creating a Hillshade from Mosaic DEM

DanPatterson_Retired — Fri, 24 Feb 2012 15:24:08 GMT

Is the mosaic projected so that the x, y and z values have the same units? If not, mosaic, project the dem, then hillshade. You may have to exaggerate the z factor if the elevation difference isn't very much relative to the x/y extent

Re: Creating a Hillshade from Mosaic DEM

EricRice — Fri, 24 Feb 2012 20:12:42 GMT

Mike,

I see that you're working with a mosaic dataset. Is there a reason you want to output a hillshade to disk, which requires storage? You can simply add the Hillshade function to your mosaic dataset and the system will generate a hillshade on the fly. As recent as this week I outlined how to add the hillshade function to a mosaic dataset containing elevation data. You can review step by step here: http://forums.arcgis.com/threads/51137-Hillshade-coming-out-totally-wrong

Regards,
Eric

Re: Creating a Hillshade from Mosaic DEM

MikeMichalek — Thu, 01 Mar 2012 20:26:56 GMT

Thanks for the input guys but I am still having difficulties. In the past I created/used a Hillshade layer behind a DEM (with a sent transparency %). Using the Hillshade option within the DEM Mosaic itself produces a different look than I'd prefer (a separate hillshade file). **You can see the difference in the attachment**

I guess what I am asking now;
Does anyone know how I can produce a Hillshade output using the Mosaic DEM, without getting the grey output?

Or can I use the Hillshade effect in the Mosaic DEM as suggested, but somehow manipulate it to produce the same thing as a DEM set with a transparency and Hillshade behind? If so, what steps would I have to take to get this function to produce what I desire? Mess with the Z Factor, ect.?

Thanks for the help,

Mike

Re: Creating a Hillshade from Mosaic DEM

EricRice — Thu, 01 Mar 2012 20:42:42 GMT

It sounds like you need to apply the Shaded Relief Function instead of the Hillshade Function on your mosaic dataset.

-Eric

Re: Creating a Hillshade from Mosaic DEM

MikeMichalek — Thu, 22 Mar 2012 11:27:10 GMT

What is the difference between a Hillshade Shade & Shaded Relief Function?

Thanks for the help,

Mike

Re: Creating a Hillshade from Mosaic DEM

EricRice — Thu, 22 Mar 2012 15:11:49 GMT

Mike,

Hillshade is black and white. Shaded Relief is a colored hillshade basically.

Eric

Re: Creating a Hillshade from Mosaic DEM

MikeMichalek — Thu, 22 Mar 2012 16:48:37 GMT

Eric,

Is there a different ArcTollbox function for the shaded relief function? If so could you please direct me to it. I know that you can create a 'color' hillshade by changing the transparency % and allowing the DEM to blend through.

Thanks,

Mike

Re: Creating a Hillshade from Mosaic DEM

JeffreySwain — Fri, 23 Mar 2012 11:51:23 GMT

Mike,

The functions that Eric is mentioning are functions after you create a Mosaic Dataset. They are not in ArcToolbox, but are available under the Function Tab when viewing the properties of Mosaic Datasets in ArcCatalog or the ArcCatalog Window.

Re: Creating a Hillshade from Mosaic DEM

FerasObeidat — Mon, 06 Oct 2014 16:17:06 GMT

Hi,

Is it possible to run Hillshade Function on local image ?

Thanks,