TierraMapper.com

[TierraMa]

Maps can be downloaded for the USA from http://terraserver.microsoft.com/default.aspx .

1.) Zoom to your area of interest.
2.) Click on Download and follow the download instructions at the bottom of the page.
3.) Save a World Header file using the directions at the bottom of the page.
**save the World Header file with the extension .jgw not jpgw.
4.) Click on Info for the map to get the datum and projection, which will be needed in Tierra Converter.
5.) Open Tierra Converter and convert the map to the Tierra Mapper format.

TerraServer maps are generally low resolution but if you have a specific area of interest a good map can be downloaded and used in Tierra Mapper.
_________________
Cheers, Mike

Tierra Mapper Support

[Mickman]

I am lost on the step to get the datum and projection. When I click Info I get coordinates around the map, that is it. I am probably missing something.

[TierraMa]

Mickman,

When you click the Info link you get coordinates around the map, but also some details on the projection below the map. It is in this section where the projection of the map is detailed, like North American Datum 1983 / UTM Zone 12N.
_________________
Cheers, Mike

Tierra Mapper Support

[Joanna]

When I click on "Info", I see the lat/long info displayed around the image but I don't see anywhere where the projection or datum are displayed. I looked below the image and on all sides.

I tried converting the image I downloaded with just the default datum and projection, and it converted okay, but then when I try to view the map on my handheld, it throws me an error of invalid latitude. I'm assuming I must have the wrong datum and projection... but where do I find it?

Thanks for the help,
Joanna

[TierraMa]

Joanna,

Follow the instructions in the first post exactly. You need to save a World Header file with the exact same name as the image you save but with the extension .jgw, so if you save the image as TerraServerMap.jpg, then save the World Header File as TerraServerMap.jgw. The World Header File looks like the below lines and tells Tierra Mapper where the image is located in space.

2.000000
0.000000
0.000000
-2.000000
516000.000000
3574000.000000

Click the Info Tab to see the projection of the image, in my test today it was; Projection: North American Datum 1983 / UTM Zone 12N which is a UTM projection, not Latitude and Longitude.

The invalid latitude error is due to you specifying the wrong projection in Tierra Converter, likely you put Lat/Long and its really UTM.

Let me know if you need more help.
_________________
Cheers, Mike

Tierra Mapper Support

[Joanna]

I was able to create the world header just fine, my problem was trying to find where it shows the projection and datum when you click on "More Info" on the map.

If you could tell me the steps to do that (I'm probably just doing something really stupid wrong), that would be helpful.

I actually got the map to work by guessing the datum and projection, though I still want to be sure they're correct.

Thanks,
Joanna

[TierraMa]

Joanna,

Click the Info link to see the projection of the image. The Info link is above the map on the right, second link to the right of the Download link. After clicking the Info link the projection info will be shown below the map.
_________________
Cheers, Mike

Tierra Mapper Support

[Joanna]

Is there any way you can post a screen shot of where you're seeing the projection and datum? I cannot find it below the map after clicking the "Info" tab.

If there was a way to attach files I could attach a screen shot of what I'm seeing. Is there a way I could email the screen shot to you?

Joanna

[TierraMa]

Joanna,

I think that maybe only in some areas is the projection displayed, maybe zoom level or area is important, but here is a link where it is displayed, http://terraserver-usa.com/ImageInfo.aspx?T=4&S=12&Z=12&X=645&Y=4467&W=1
_________________
Cheers, Mike

Tierra Mapper Support

[Joanna]

Ah yes, I see it there.

Here's the link to what I was viewing:
http://terraserver-usa.com/ImageInfo.aspx?T=1&S=12&Z=10&X=703&Y=6667&W=1

Strange! I'll just go with my guesses, then. They appeared to work just fine.

Thanks for the help,
Joanna