I am wondering if I could merge DEM and Hillshade? What are the pros and cons for that?
-
possible duplicate: gis.stackexchange.com/questions/19386/…– Jakub Sisak GeoGraphicsOct 17, 2012 at 19:59
-
For now I don't have the ArcGIS 10– PROBERTOct 17, 2012 at 20:12
-
I removed all the ArcGIS tags to reflect the lack of ArcGIS software to carry out a solution and to keep this from being a duplicate of the previous ArcGIS-oriented question.– whuberOct 17, 2012 at 21:15
-
1What end-product do you hope to produce? After all, hillshades are derived from DEMs.– Aaron ♦Oct 17, 2012 at 21:27
-
Listen all, I got my ArcGIS 10 upgrade. Finally and I was able to perform Elevation and Hillshade just exactly what I wanted ! I created one Desert tint hillshade ! Thanks.– PROBERTNov 7, 2012 at 22:01
Add a comment
|
3 Answers
Combined pan-sharpening, contrast stretching, and gamma stretching functions
If you have access to ArcGIS (and the Spatial Analyst Extension) you can use the technique described in this blog to "blend" DEM (or imagery) with shaded relief. The main disadvantage of this solution is that it is static; you need to produce an RGB raster from your DEM so if you need to change the original symbology in any way you have to do it on the original DEM raster then re-do the RGB raster and repeat all the steps. Luckily 95% of my current work is in the same geographical area so I just built various models and schemas that suit the various scales I often use and simply copy and paste them in the map as needed. As for using this approach with imagery; one unexpected advantage beyond just the wow factor is that field crews and environmental scientists like that use these "imagery-hill-shade blend" maps to get a sense of the terrain characteristics as well as the aerial perspective in one glance.
As a side note; It does require a certain amount of tinkering around with the functions to get the look of the resulting layer just right.
Below is an example and the input rasters. The last image is an example of imagery "blended" with DEM. No transparency was applied, the below examples are a result of the above mentioned functions as described in the linked ArcGIS Resource Centre blog by rajnagi.
DEM & Hillshade:
Input DEM:
Input Hillshade:
Imagery & Hillshade example:
answered Oct 18, 2012 at 13:38
Jakub Sisak GeoGraphicsJakub Sisak GeoGraphics
20.3k20 gold badges104 silver badges180 bronze badges
-
Thanks for the info. I don't know if this will work with 9.3.1. I don't have the 10 yet.– PROBERTOct 18, 2012 at 14:45
-
-
You could 'merge' dem and hillshade. You could add 1 (grayscale or colormap) or 3 (rgb) bands to the dem. I don't see any benefit to doing so, and it would probably cause confusion given 2 band images are rare and 4 band images will likely at some point be misinterpreted as and RGBA image. Personally, I wouldn't do it.
-
How do I do that ? Do you mean the grayscale or bands from the Landsat ?– PROBERTOct 17, 2012 at 19:14
-
My thinking is to export each DEM and Hillshade and then merge both is that what you meant ?– PROBERTOct 17, 2012 at 19:47
-
Sorry, I may have misunderstood. Where does landsat come it? Some hillshades can be colored as in the example below, that is where 3 bands come in. DEMs are usually a single band with z values.– user10353Oct 18, 2012 at 16:23
In ArcGIS you can apply a hillshade effect to a DEM - it's a check box on the Symbology tab under Properties.
This will allow you to keep the values in the DEM, but still allow for the visual effect of the hillshade.
