DEM in Meters and Feet

[Anonymous]

I've got a 30Meter DEM file downloaded from Labins, Converted using sdts2dem. the files lists with two different untis, meters horizontal and feet for elevation. I'm ending up with 30 ft contours where there shoudn't be anything over 10. LDT drawing is set up as FL83-NF, and the hroizontal information looks correct, the ocean is where it's supposed to be, and the land is in the right location. but there are'nt any 30 ft hills in this area of the state.

Is there any way to rationalize this so the elevations don't get hosed and scaled up?

from the DEM file properties
Coordinate System Type UTM
Zone 16
Horizontal Datum NAD 27
Vertical Datum NGVD 29
Vertical Datum Shift 0.000000
DEM Level 1
X-Y Units meters
Elevation Units feet
Minimum Elevation 0.000000
Maximum Elevation 33.000000

[Anonymous]

Did you set things properly in the Drawing Setup>Zone tab cadtag?

United States is unfortunately quite a ways down the list of "environs", but
then the States are easily found after that. The last item is to get your
particular "vicinity" sufficiently positioned, meaning correctly. 😉

HTH

--
Don Reichle
"The only thing worse than training your staff, and having them leave is -
not training your staff, and having them stay." 😮
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wrote in message news:5423483@discussion.autodesk.com...
I've got a 30Meter DEM file downloaded from Labins, Converted using
sdts2dem. the files lists with two different untis, meters horizontal and
feet for elevation. I'm ending up with 30 ft contours where there shoudn't
be anything over 10. LDT drawing is set up as FL83-NF, and the hroizontal
information looks correct, the ocean is where it's supposed to be, and the
land is in the right location. but there are'nt any 30 ft hills in this
area of the state.

Is there any way to rationalize this so the elevations don't get hosed and
scaled up?

from the DEM file properties
Coordinate System Type UTM
Zone 16
Horizontal Datum NAD 27
Vertical Datum NGVD 29
Vertical Datum Shift 0.000000
DEM Level 1
X-Y Units meters
Elevation Units feet
Minimum Elevation 0.000000
Maximum Elevation 33.000000

[Anonymous]

Hi Don,

LDT is set to FL83-NF, and the horizontal location of the incoming contours is fine - LDT is handling the transformation of Meters is the DEM file to Feet in the drawing properly. unfortunately, it's applying the same transformation to the elevation data, which is in the DEM file in feet.

Somehow, I need to either get LDT to ignore the conversion on the Z data, or somehow convert the DEM to use consistent units for both horizontal and vertical control.
LDT 2006, SP1

[Anonymous]

Did you try searching the Knowledgebase and this NG on the Web side? I think
I recall seeing this discussed quite some time ago. A few years ago maybe.

--
John Mayo
Project Engineer
Conklin Associates
Ramsey, NJ

Civil 3D 2007, LDT 2007, Raster Design 2007
P-IV at 3.5 GHz
2 GB Ram
Nvidea Quadro FX w/ 128 MB Ram
wrote in message news:5424982@discussion.autodesk.com...
Hi Don,

LDT is set to FL83-NF, and the horizontal location of the incoming contours
is fine - LDT is handling the transformation of Meters is the DEM file to
Feet in the drawing properly. unfortunately, it's applying the same
transformation to the elevation data, which is in the DEM file in feet.

Somehow, I need to either get LDT to ignore the conversion on the Z data, or
somehow convert the DEM to use consistent units for both horizontal and
vertical control.
LDT 2006, SP1