How to Get Real Height Data

[Sandhapper]

Can someone make a video tutorial? cuz i want to make good tracks too, but i dont understand the tutorial

[BrutalMX]

How do I find exactly where my track needs to be in the QGIS application? I have a general idea, but only by looking at the river running near the track I need to make, and also only by trying to make the Coordinates line up with the coordinates of the track.

I tried the Seamless Viewer on the site...but for some reason the area that I pick, which is in Northeast PA, it keeps saying there is no data to download.

ALL I need is a decent disp of the track im going to make. It seems like there are so many way to go about it, and Im not sure which to pick. QGIS? Seamless Viewer? OR stick with MicroDem? Someone PLEASE HELP

[Motoboss]

Wish I could help ya man but I havnt used any of those programs ...Hag would be the man to ask Im sure ,Maybe try to PM him.

[haggqvist]

The method using QGIS I described above isn't working and the best way to access the NED dataset is to use the seamless viewer at USGS.

This is the method you should use:

Here's a brief description of how I go about it:
- Find the area of interest.
- Click the download button in the right pane.
- Mark the area you want to download data for with the "Define rectangular download area"-button and a new window opens.
- Click "Modify data request".
- At the bottom, change the value of "Maximum size per piece" to 250MB.
- Check the boxes next to the files you're interested in, typically all the orthophotos listed and the 1/3 and 1/9 dem files. For the dem-files, change the data format to geotiff.
- Click "Save changes and return to summary".
- Download the files from the request summary page.
- Open the geotiff dem in microdem. Don't resize it! Just convert it to grayscale, make a note of the z-range for the terrain.hf. and save as .png.
- Open the .png in ps and change it to 16bit.
- Paste the orthophoto in the same .psd.
- Now you have a base disp, with a perfectly aligned orthophoto as a reference, that can be cut down to whatever size you want.

If it says that the data is unavailable it is possible that the servers are down momentarily, that has happened to me on several occasions. Check the system status here.

[SCHAFFERNOCKER]

When I tried it I think to get the original DEM data I used this little google earth plugin http://www.ambiotek.com/topoview basically overlays all the regions of data on google earth and you can download straight from there. Hope this helps somebody

Once I have found my section and downloaded the data, which already comes in a .tif format

I'm not sure where to go from here, how do I get my elevation data from this .tif file? Microdem does not allow me to open this...

[haggqvist]

Microdem is able to open those files, just go to file>open>open DEM. You don't even have to unzip the file first.

What area are you trying to get data for?

[SCHAFFERNOCKER]

Im working on trying to data for some local tracks in my area. I dont have the coordinates since im at work but the physical track address is: 1258 Panda Rd. SE - Carrollton, Ohio




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[haggqvist]

Then you should get NED data and aligned orthoimagery directly from USGS using the method I described above.
The SRTM data you get by using that Google Earth plugin only has a resolution of 90m compared to the 3m and 10m resolutions of the 1/3 and 1/9 arcsecond NED datasets.

SRTM data is only useful for the rest of the world where all data of higher resolution is commercial.
Getting an aligned orthophoto for the SRTM data is also a lot more difficult and requires a fair bit of voodoo...

[ddmx]

Im working on trying to data for some local tracks in my area. I dont have the coordinates since im at work but the physical track address is: 1258 Panda Rd. SE - Carrollton, Ohio




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That's not 330 is it?

[SCHAFFERNOCKER]

yup... you already working on this one too ddmx?

[m121c]

Well since no one wants to reply to my topic in the track editing forum I guess I'll post it here to. I would like for someone to help fast so I can start working on it.

I want to make a replica of a local track in Illinois called Sunsetridge Mx. I have rode it irl many times so I know what is like and that it would be fun to have in mxs. I am having trouble understanding the way to get the replica terrain. I tried followinig the tutorial from "How to get real Height Data". I tried following haggqvist's tutorial that he had in one of the posts cause it seemed like that was the best way to do get the terrain. I just need help with understanding it. I found the area I want on google earth then I found it on the seamless viewer USGS. I dont know if the next parts I did correct or not. I selected the 1 1/3 and 1/9 DEM files and put them as geotiff. I selected all the ortho images which was about 25 zones of the area? (black and white photos) When I put the DEM into microdem (I read to look at the z-range for the terrain.hf but I don't understand that) and convereted it to a greyscale image and then put into photoshop the ortho image was huge compare to the terrain, and the terrain had a scale of the height. The terran also showed no resembelance of jump tips or anything (I didnt know if it was suppossed to). I also don't understand once I get this figured out how to I put the orthoimage into the game? So that it sits on top of the terrain? Set it as a decal?

If anyone can help thanks in advance.
If anyone is interested in the coordinates it is: 41 30 12.44 N| 89 38 22.54 W
There website and address can be found here: http://www.sunsetridgemx.com
I can also post the images if it is needed.

[yzmxer608]

Did you change the display parameter in Micro Dem to elevation using the gray scale option? The ortho image should be the same scale and match perfectly with the terrain, if the terrain isn't 1/9 you most likely won't get any definition of any of the track, just the base terrain around it.

[m121c]

Ya idk which DEM I downloaded.(I think it was 1/3) When I resized the terrain in photoshop to the same size of the ortho image everything lined up. There was no track definition at all. Then I put the ortho image into shadingx2.ppm and saved the terrain. Went into the game and the terrain was really bumpy and wasnt right. The track was way to small then what it is irl. I have the scaling wrong but how do you get the scaling correct to match the track. If you make the picture bigger and change it from 1025 to 2049 wont the track become disproportioned? The ortho image is from a pretty good elevation height too, is there a specific height you need to take it from? I need more in detail steps on how to accomplish getting the terrain and then putting it into the game with the correct scaling if that would be possible.

[haggqvist]

Download Budds Creek from this post and have a look at the source files in the folder ../budds.creek/terrain/ and the files in the track folder ../budds.creek/budds.creek.2011/; that will probably answer most of your questions.
To calculate the terrain.hf scale you can use the spreadsheet included (../budds.creek/terrain/disp.scale.calculation.ods) as a template and follow the description here.

As for how to use the reference orthophoto; I would recommend placing it as a semi-transparent decal instead of using the shadingx2 as any changes to the terrain in the editor will remove it.

I'm planning on writing a proper in-depth tutorial later that will include the use of SRTM data as well, but right now I'd rather use what little time I have to work on the GP- tracks.

[yzmxer608]

That would be great Hagg! I use the seamless viewer method now instead of the method in the first post.