10 ft Contour Maps

Cartography, maps, navigation, GPS and more.
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BrianEdwards
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10 ft Contour Maps

Post by BrianEdwards » December 3rd, 2012, 12:25 pm

Regarding this map:

Image

I am curious how to obtain this, and if its very accurate. This map mixed with Lidar and a good aerial image should give a good representation of what's out there.
Clackamas River Waterfall Project - 95 Documented, 18 to go.

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retired jerry
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Re: 10 ft Contour Maps

Post by retired jerry » December 3rd, 2012, 12:28 pm


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BrianEdwards
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Re: 10 ft Contour Maps

Post by BrianEdwards » December 3rd, 2012, 12:39 pm

Thanks Jerry. Looks like I'll be signing up if others on PH's decide to as well.
Clackamas River Waterfall Project - 95 Documented, 18 to go.

RexSe7en
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Re: 10 ft Contour Maps

Post by RexSe7en » December 3rd, 2012, 3:09 pm

BrianEdwards wrote:Thanks Jerry. Looks like I'll be signing up if others on PH's decide to as well.
I plan to sign up and I know a few others have talked like they plan to attend as well. Sign up and we'll see you there!!! Hopefully someone will be able to chime in on a good source.

Adventure Mapper
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Re: 10 ft Contour Maps

Post by Adventure Mapper » December 4th, 2012, 1:03 am

The 10 ft. contour lines are generated from the same LiDAR data that is viewed "under the contours" as a hillshade. I can't find the complete metadata but the underlying LiDAR data is certainly more accurate than any handheld GPS receiver, probably less than a meter. The data is available from the Oregon Geospatial Enterprise Office but it comes in a seldom used format called a "coverage" (.adf). A GIS program such as Global Mapper or QGIS or ArcMap is needed to work with data in this format. Once a DEM (Digital Elevation Model) is loaded, GIS programs can generate contour lines at any interval.

For a few areas LiDAR data is available as 1/9th arcsec DEM (Digital Elevation Model) or hillshade from the National Map. Also, DOGAMI has a LiDAR viewer. It is somewhat easier to view data from these sources but you will find it difficult to overlay your tracks and/or aerial photos without a viewer that can geo-reference the data.

What I hope to do in my class at PCC http://www.pcc.edu/schedule/default.cfm ... topicCode=
is to give people a basic understanding of cartography and GIS so they can get past the ugly details of getting geographic data. Once people are comfortable with geographic data they can use their own creativity to make custom maps to suit their own purpose. Understanding geographic data and cartography is like understanding geology or botany or photography. It enhances the wilderness experience.

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Re: 10 ft Contour Maps

Post by Adventure Mapper » December 4th, 2012, 1:21 am

I found the metadata for the LiDAR data of the Lester Creek area.
Attachments
000_000_fill_metadata.txt
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BrianEdwards
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Re: 10 ft Contour Maps

Post by BrianEdwards » December 4th, 2012, 9:47 pm

Thanks for the time and info Jay. Now that I know you're a teacher, I'll stop trying to get secrets out of ya :P Never expected it
Clackamas River Waterfall Project - 95 Documented, 18 to go.

Adventure Mapper
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Re: 10 ft Contour Maps

Post by Adventure Mapper » December 4th, 2012, 11:46 pm

I'm not a teacher by profession. I just happen to know some about cartography for wilderness exploration. My PCC class is community education so anyone can take it.

I was able to get 10 ft. contours made using only publicly available data and free software tools. The resulting files are too large to send and the underlying LiDAR data has gaps so I won't work on it more but I'm glad to know it can be done.

I'm happy to help with cartography when I can.

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